bluuebunny/crossref_metadata_2025 huggingface dataset:
Overview of the relationship between structure and functin in ion channels
Authors: McDonough Stefan , Lester Henry A.
Published: January 2005

This review briefly introduces the known classes of ion channels, describes conceptual insights gained from structure‐function work, and discusses the limitations of the techniques use. Finally, unresolved issues and promising future directions are highlighted. © 1994 Wiley‐Liss, Inc.
Function and structure of voltage‐dependent potassium channels
Authors: Wible Barbara A. , Brown Arthur M.
Published: January 2005

Voltage‐dependent potassium (K+) channels are the largest group of voltage‐dependent ion channels and more cDNAs have been cloned for voltage‐dependent K+ channels than for voltage‐dependent Na+, Ca2+, and Cl− channels, the other main categories of voltage‐dependent ion channels. The cloning result was anticipated from electrophysiological measurements because K+ currents are by far the most diverse of voltage‐dependent ion currents. In this review K+ currents will be classified functionally first and structurally second, an arrangement that follows the historical development of the field. Then, we will examine present attempts to assign the major functions of voltage‐sensing, gating and ion conduction to specific domains of K+ channel proteins. Finally, we will describe present understanding of drug interactions with the ion conduction pathway or pore of K+ channel proteins. © 1994 Wiley‐Liss, Inc.
Advances in the structure‐activity relationships, mechanisms of action, and therapeutic utilities of ATP‐sensitive potassium channel openers
Authors: Atwal Karnail S.
Published: January 2005

The presence of ATP‐sensitive potassium channel (KATP) in a variety of tissues makes it an important therapeutic target for drug research. The existence of small molecules that modulate its activity has attracted a great deal of attention over the past several years. Progress achieved at understanding the structure‐activity relationships of KATP openers, and their therapeutic utilities and mechanism of action are summarized in this review. The compounds combining the features of potent KATP openers cromakalim, pinacidil, and aprikalim retain the biological profiles of their predecessors, indicating the classical KATP openers may be expressing their biological effects through similar structural requirements. Based on these studies, a pharmacophore model which incorporates a lipophilic residue, an electron deficient aromatic ring, and a hydrogen bonding site has been proposed. Although the first generation compounds have served as extremely useful tools., their therapeutic utility is limited due to indiscriminate actions in a variety of tissues. Tissue selective KATP openers are required to advance these compounds into clinical practice. Progress made at the discovery of selective KATP openers that might be useful for the treatment of ischemic heart disease, urinary incontinence, and asthma is described in this article. The molecular mechanism of action of KATP openers is far from being understood. A binding site for these agents has been identified in the rat aortic smooth muscle cells and intact rat aortic tissue. However, the relationship of this binding site to KATP is not understood at the present time. Further work is needed to explore the clinical utility of tissue selective agents and understand their molecular mechanism of action. © 1994 Wiley‐Liss, Inc.
Activators of voltage‐dependent L‐type calcium channels
Authors: Rampe David , Michael Kane J.
Published: January 2005

The L class of voltage‐dependent Ca2+ channels provides an important pathway for Ca2+ entry into a variety of excitable cells. Many drugs have been shown to be blockers of this channel including the clinically available nifedipine, verapamil, and diltiazem. An increasing number of compounds are now being recognized as activators of L‐type Ca2+ channels. The best characterized of these are certain 1,4‐dihydropyridines, typified by Bay K 8644, which act as partial agonists of the channel. The benzoylpyrrole group of molecules, which includes FPL 64176, have proven to be highly efficacious L channel agonists. Certain naturally occurring substances, ranging from toxins to endogenous ligands, have also been proposed as activators of this channel. Activators of L‐type Ca2+ channels have proven to be valuable tools with which to study the structure and function of these channels and could lead to the development of new therapeutic entities. © 1994 Wiley‐Liss, Inc.
Synergistic effect on reduction in blood pressure with coadministration of a renin inhibitor or an angiotensin‐converting enzyme inhibitor with an angiotensin II receptor antagonist
Authors: Fossa Anthony A. , Depasquale Michael J. , Ringer Laura J. , Winslow Roxanne L.
Published: January 2005

The effects of coadministration of a renin inhibitor, terlakiren, and an angiotensinconverting enzyme inhibitor, captopril, with the angiotensin II receptor antagonist, losartan, on blood pressure of sodium‐depleted guinea pigs were studied. Dose‐response relationships for terlakiren (0.1 to 3.0 mg/kg, iv), captopril (0.03 to 1.0 mg/kg, iv), and losartan (0.1 to 6.0 mg/kg, iv) were obtained either alone or in the presence of a submaximal dose of the other inhibitor. The hypotensive response calculated for each compound individually was subtracted from the response to each dose of the combination of inhibitors, and the results showed that statistically significant synergy with terlakiren and captopril occurred in the presence of losartan. The degree of the synergy indicated that to achieve the same response on blood pressure, the dose of each drug could be decreased approximately 2‐ to 7‐fold when administered in combination. These results indicate that by inhibiting multiple sites in the renin‐angiotensin system, synergistic effects can be produced. The relative safety of each inhibitor could be improved by large reductions in dose when used concurrently. © 1994 Wiley‐Liss, Inc.
New 1,4‐benzothiazepine derivative, K201, demonstrates cardioprotective effects against sudden cardiac cell death and intracellular calcium blocking action
Authors: Kaneko Noboru
Published: January 2005

In order to find drugs with suppressive effects against sudden cardiac cell death due to myofibrillar overcontraction, the cardioprotective effects of a new 1,4‐benzothiazepine derivative, 4‐[3‐{1‐(4‐benzyl)piperidinyl}propionyl]‐7‐methoxy‐2,3,4,5‐tetrahydro‐1,4‐benzothiazepine, K201, in comparison with five other compounds, including a representative α‐antagonist, β‐antagonist, and Ca2+ channel antagonists, were investigated in an experimental myofibrillar overcontraction model of isolated rat heart. In addition, the effects of K201 on the contraction of isolated vascular smooth muscle of rat aorta and on the binding of cardiac annexin V with actin were compared with those of diltiazem and KT362. The degree of myofibrillar overcontraction was histologically scored on a four‐grade scale (0, 1, 2, and 3) as myocardial injury score (MIS). Suppressive effects of myofibrillar overcontraction could not be observed with nicorandil and prazosin at 10−5 M. Propranolol at 10−5 M, verapamil at 10−6 M, and diltiazem at 10−6 M demonstrated a significant suppressive effect with MIS of 1.0 ± 0.4 (P < 0.01), 1.5 ± 0.3 (P < 0.01), and 1.5 ± 0.3 (P < 0.01), respectively. K201, even at 10−7 M, displayed significant suppression with MIS of 1.8 ± 0.2 (P < 0.01). K201 inhibited contraction of isolated vascular muscle induced by K+ (40 mM) and NE (1 μM) at almost the same concentration. The lC50 ratio (NE/K+) of K201 was 2.3. The inhibition by K201 of the response to K+ was less marked than that by diltiazem. Its inhibition of the response to NE was greater than that by diltiazem or KT362. K201 demonstrated an inhibitory effect on binding of cardiac annexin V with actin dependent on calcium concentration, but diltiazem and KT362 did not demonstrate any action to inhibit this reaction. These results indicate that K201 was a more effective cardioprotectant than propranolol, verapamil, and diltiazem in the experimental myofibrillar overcontraction model. K201 has intracellular Ca2+ blocking action in addition to weak α‐1 adrenergic blocking activity and Ca2+ blocking activity. © 1994 Wiley‐Liss, Inc.
Some practical considerations and applications of the national cancer institute in vitro anticancer drug discovery screen
Authors: Boyd Michael R. , Paull Kenneth D.
Published: January 2005

During 1985–1990 the U.S. National Cancer Institute (NCI) phased out its murine leukemia P388 anticancer drug screening program and developed as the replacement a new in vitro primary screen based upon a diverse panel of human tumor cell lines. For each substance tested, the screen generates a remarkably reproducible and characteristic profile of differential in vitro cellular sensitivity, or lack thereof, across the 60 different cell lines comprising the panel. Several investigational approaches to display, analysis, and interpretation of such profiles and databases, derived from the testing of tens of thousands of substances during the past 4–5 years since the NCI screen became fully operational, have been explored. A variety of useful, practical applications of the in vitro screen have become apparent. As these applications continue to evolve, they are proving to be complementary to diverse other anticancer screening and drug discovery strategies being developed or pursued elsewhere. Reviewed herein are some practical considerations and selected specific examples, particularly illustrating research applications of the NCI screen that may be more broadly applicable to the search for new anticancer drug development leads with novel profiles of antitumor activity and/or mechanisms of action. © 1995 Wiley‐Liss, Inc.

This article is a US Government work and, as such, is in the public domain in the United States of America.
Human thrombin receptor‐activating peptide‐induced proliferation of cultured vascular smooth muscle cells exhibits species specificity
Authors: McNamara Coleen A. , Sarembock Ian J. , Gimple Lawrence W. , Fenton John W. , Owens Gary K.
Published: January 2005

Thrombin receptor stimulation in vitro signals many cellular events that are associated with the response to vascular injury in vivo. Indeed, we have previously shown that human α‐thrombin and the 14‐amino acid human thrombin receptor‐activating peptide (huTRAP‐14) stimulate proliferation of cultured rat aortic smooth muscle cells (SMC). In the present studies, the mitogenic response of rabbit vascular SMC to thrombin and huTRAP‐14 was assessed using [3H]thymidine incorporation and cell number. Results demonstrated that thrombin stimulated mitogenesis of rabbit vascular SMC in culture and that the thrombin response was dependent on proteolytic activity. However, huTRAP‐14 was not mitogenic for rabbit vascular SMC. Thus, there are species differences in huTRAP‐14 responsiveness. As rat and rabbit models continue to be used extensively to evaluate mechanisms and potential therapies for human restenosis, it is important to identify any species differences in the mechanism whereby thrombin exerts its biological effects. © 1995 Wiley‐Liss, Inc.
Stimulation of nitric oxide synthesis in macrophage cell line raw 264.7 cells by several traditional chinese herbal medicines
Authors: Izumi Shigeru , Ohno Naohito , Miura Noriko N. , Takada Katsutoshi , Yadomae Toshiro
Published: January 2005

The effect of 18 traditional Chinese herbal medicines [Kampo medicines (KMs)] on nitric oxide (NO) synthesis in vitro was assessed by using macrophage cell line RAW 264.7 cells. All of the prescriptions enhanced NO synthesis, and eight prescriptions showed strong activity relative to the other remaining prescriptions. After dialysis of the water‐soluble part of the prescriptions, the retaintate showed significant activity, suggesting that macromolecular fractions enhanced NO synthesis. Egg white lysozyme, which can bind to lipopolysaccharide (LPS) and neutralize its biological activities, abrogated NO synthesis of a part of the macromolecular fractions. These results suggest that KM‐stimulated NO synthesis was independent of the contaminated LPS. The NO synthesis was inhibited by NG‐monomethyl‐L‐arginine acetate, an inhibitor of nitric oxide synthase (NOS), showing that induced NO resulted from the activation of inducible NOS but not from nitrite in crude drugs. © 1995 Wiley‐Liss, Inc.
Maternal food restriction: Effects on offspring behavior and development
Authors: Ottinger Donald R. , Tanabe Gilfred
Published: January 2005

Pregnant rats were placed on reduced food intake or remained on adequate diet during gestation and lactation. Offspring were cross‐fostered to provide for independent experiences of prenatal and/or postnatal mother malnutrition. All offspring were placed on an ad lib diet at time of weaning. When evaluated in adulthood, offspring whose mother was food‐deprived during the lactation period showed body weight deficits and increased errors on the Hebb‐Williams maze as compared to controls. There were no observed effects of the prenatal deprivation.
Mice reared with rats: Elimination of odors, vision, and audition as significant stimulus sources
Authors: Denenberg Victor H. , Paschke Richard , Zarrow M. X. , Rosenberg Kenneth M.
Published: January 2005

Prior research has found that mice reared and nursed by a lactating rat mother, or reared in the presence of a nonlactating adult female rat, give a significantly smaller adrenocortical response to a novel stimulus than do control mice. The purpose of this paper was to determine whether this phenomenon could be mediated through stimuli that do not require physical contact between the adult rat and the young mouse. Experimental mice were born and reared in a cage that separated them from an adult nonlactating female rat by means of a double mesh wall. Thus, they could see, hear, and smell the rat, but no physical contact was possible. Control mice were reared similarly in the presence of an adult nonlactating female mouse. At the time of weaning the corticosterone response of both groups to a novel stimulus was virtually identical. The data support the hypothesis that direct physical contact between the mouse and rat is necessary to cause physiological and behavioral changes in the mouse.
Postnatal behavioral alterations resulting from prenatal administration of d1‐alphamethylparatyrosine
Authors: Lydiard R. B. , Sparber S. B.
Published: January 2005

We have previously reported that injection of d1‐alphamethylparatyrosine methylester (AMPT) into the yolk sac of fertilized chicken eggs prior to incubation results in dose‐related increases in the specific activity of tyrosine hydroxylase (TH) at 29 days postnatally. We now report that injection of 10.0 and 33.3 mg/kg of AMPT prior to incubation results in dose‐related increases in acquisition rates of 2 operant responses. Between 1 and 3 weeks of postnatal age, we observed a dose‐related decrease in latency to perform a detour response and, at 55–60 days of postnatal age, an increased rate of acquisition of a key peck response in an autoshaping paradigm. We could not discern any significant alteration in several measures of unconditioned behaviors in an open field situation at 3 weeks of postnatal age. Our data support the contention that early catecholamine (CA) depletion can produce long‐term alterations in postnatal behavior.
Development of locomotion toward home nesting material in neonatal rats
Authors: Szerzenie Victoria , Hsiao Sigmund
Published: January 2005

Neonatal rats were individually placed in a narrow choice zone between home and fresh nesting materials. At Day 2 postpartum the pups made significantly more home‐choosing responses (vs responses for fresh nesting material). At a mean of 5.6 days (range, 4 to 9 days) the pups reached a criterion of 2 consecutive days of responses all for home nesting material. The number of head contacts increased abruptly upon reaching the criterion. In a 2nd experiment we observed that the pups which were repeatedly tested performed no better than those which were tested for the 1st or the 2nd time. Thus, (a) home‐seeking responses appear to emerge substantially earlier than previously reported by other investigators, (b) head‐contact responses appear to be related to successful home‐choosing, and (c) some maturational rather than experiential factors are important for the development of both head‐contact and home‐choosing responses.
Effect of handling on maternal behavior following return of pups to the nest
Authors: Villescas Ramiro , Bell Robert W. , Wright Linda , Kufner Michael
Published: January 2005

Handling rat pups during the 1st week after birth altered adult behavior in the open‐field, whereas simply separating the pups from their mothers during the same period produced differences in body weight at weaning. Observations of mother‐infant interaction following pup treatment yielded different patterns of maternal behavior. Moreover, pups receiving early treatment were more active as adults in a novel environment and had a greater body weight at weaning. The quality of maternal care and the immediate effects of infantile stimulation on the mother‐infant relation should be considered in specifying a mediating mechanism for the effects of early experience.
Effects of parental environment on the prevalence of convulsive seizures in Onychomys torridus
Authors: McCarty Richard , Southwick Charles H.
Published: January 2005

Male and female southern grasshopper mice (Onychomys torridus) were reared in 1 of 3 different parental environments: (a) with the natural male and female parents; (b) with the female parent only; or (c) with foster parents of a closely related species, Peromyscus leucopus. All mice were weaned at 25 days of age, then observed individually in an open field arena at 10‐day intervals from 30 to 100 days of age. Twenty‐seven of 59 subjects (45.8%) that were reared by the natural parents exhibited convulsive seizures during at least 1 of the 8 tests in the open field arena. The prevalence of convulsive seizures increased significantly in subjects that received altered parental care: 27 of 41 subjects (65.9%) reared by the female parent only or by Peromyscus foster parents seized during at least 1 of the 8 tests in the open field. Subjects from the 3 treatment groups did not differ in the mean number of seizures observed during the 8 open field tests. These results demonstrate a significant influence of the preweaning parental environment on the prevalence of convulsive seizures in Onychomys torridus.
Construction of low‐variability litters of preweaning mice
Authors: Epstein Herman T. , Goldstein Larry B.
Published: January 2005

Mouse litter variation at weaning stems from a combination of genetic makeup, intrauterine experience, and postnatal maternal care. The 1st 2 factors may be matched at birth by making up separate litters out of littermate pairs whose birth weights are equal (± .02 g). Maternal competence may be matched by exchanging the mothers between the 2 cages each day. These tactices yield litters at weaning whose variability has been very much reduced. The range of litter‐average body weights has been reduced from about 40% to about 5% and the range of litter‐average brain weights has been reduced from about 15% to about 1‐2%.
Species‐specific auditory discrimination in bobtail quail neonates
Authors: Barrow Heaton Marieta , Miller David B. , Goodwin Donna G.
Published: January 2005

Incubator‐hatched bobwhite quail neonates were tested individually in a variety of single call and simultaneous auditory choice tests involving 6 adult quail vocalizations and a chicken exodus call. The quail showed a high degree of responsiveness (100%) to 3 adult quail vocalizations and significantly less responsiveness (40–50%) to 3 other quail calls and to the chicken exodus call in single call tests. In simultaneous choice tests, the quail were selectively responsive to a call of their own species over the chicken call, and they also showed certain intraspecific preferences. Because of their high degree of responsiveness, coupled with the selectivity of their approach responses, bobwhite quail neonates are ideal for the laboratory investigation of the development of auditory perception.
Effects of undernutrition in neonatal rats on physical development and food and water regulation
Authors: Look Jared Jay
Published: January 2005

The effects of neonatal undernutrition in rats on food and water regulation, external indices of development, and long‐term regulatory behavior were investigated. Undernutrition produced retardation in some external indices of development. The ability to eat, drink, and maintain body weight at weaning were not seriously affected by the undernutrition. Longer term deficiencies in feeding efficiency, osmotic regulation, prandial drinking, and activity were found for experimental subjects. The involvement of peripheral‐systemic factors as well as neurological retardation in producing feeding and drinking deficits following undernutrition are discussed.
Lateralization in normal 6‐year‐olds as related to later reading disability
Authors: Kershner John R.
Published: January 2005

The differentiation of lateral preference in hand, eye, ear, and foot was measured in 110 normal Grade 1 children and reading achievement was tested 3 and 5 years later. No support was found for the widely held belief that delays in early lateralization underlie subsequent reading impairment. Paradoxically, boys with serious reading disability showed a strong degree of early lateral concordance. Male, impaired readers displayed a tendency when they were in Grade 1 to be either uniformly right‐ or left‐preferring across all 4 sensory‐motor modalities. The results contradict the popular notion that lateral usage emerges from an undifferentiated state in the direction of greater degrees of specialization. Lateralization may be an expression of reflex constraints bound initially to the infant's tonic‐neck posture, with later development less reflex‐patterned during the acquisition of more sophisticated information‐processing strategies. Such an interpretation implies a progressive discontinuity between lateral usage and neuro‐maturational processes. Alternatively, the results can be accounted for by (1) a new maturational delay model in which maturation‐dependent lateralization proceeds in graduated stages from a highly specialized beginning toward greater levels of neuromotor integration; or (2) a model that maintains the notion of emergent lateralization but in which delays in the lateralization process are actually beneficial to later performance.
Physiological correlates of maternal separation in surrogate‐reared infants: A study in altered attachment bonds
Authors: Reite Martin , Short Robert , Seiler Conny
Published: January 2005

Three pigtail infant monkeys (Macaca nemestrina) were separated from their mothers shortly after birth and raised in social isolation on cloth surrogates. At about 24 weeks of age they were surgically implanted with multichannel biotelemetry systems. Following the collection of baseline behavioral and physiological data, the cloth surrogates were removed for 4 days, then returned. The behavioral and physiological (heart rate, body temperature, sleep patterns) reaction to separation from the surrogate was much less intense than is the case in group‐living pigtail infants that are separated from their mothers, suggesting that the attachment bond to a cloth surrogate may well be different than the bond to a living mother in a social group. Heart rate mean values and variability were similar in surrogate‐reared and mother‐reared infants, suggesting a degree of environmental independence in heart rate regulation.
The effect of neonatal oil administration on brain weight of inbred and heterogeneous mice
Authors: Blizard David A.
Published: January 2005

A single injection of sesame oil on postnatal Day 4 reduced adult brain weight in male and female mice of the C3H/HeJ strain. The same neonatal treatment had no effect on brain weight of heterogeneous mice derived from a cross of 8 inbred strains. In agreement with previous findings in inbred strains, C3H/HeJ females were found to have larger brains than males. This difference between the genders was not seen in heterogeneous mice. The effect of neonatal oil administration on adult brain weight provides an additional example of the effect of neonatal manipulations on the adult organism and underscores the importance of adherence to appropriate control procedures in studies involving administration of hormones in early life, particularly when inbred strains are used as experimental subjects.
Behavioral persistence following switchovers between environmental enrichment and impoverishment in mice
Authors: Klippel Judith A.
Published: January 2005

Weanling mice were reared in environmental enrichment and/or impoverishment conditions for 2 months. In the 1st experiment, mice were switched from 1 environment into the other after 1 month, and maintained in the opposite environment for 2 or 4 weeks. Switched and nonswitched groups were compared to establish whether the effects of the initial environmental exposure would persist through later opposite environmental experiences. The performance of switched groups tended to differ from that of all nonswitched groups: little behavioral persistence was found. In the 2nd experiment, mice were switched every 7, 14, or 28 days over a 2‐month period. These procedures yielded several types of behavioral outcomes; however, no behavioral persistence was evidenced. The data indicate that early life experiences in a particular level of environmental complexity need not permanently modify behavior.
Self‐recognition and stimulus preference in autistic children
Authors: Neuman Cynthia J. , Hill Suzanne D.
Published: January 2005

A common notion regarding autistic children is that they do not show self‐recognition. In this study, 7 autistic children were compared to a group of normal infants at the age of self‐recognition. Using a videotape “mirror image” and an objective self‐recognition criterion, we observed that 6 of the 7 autistic children exhibited self‐recognition. In a 2‐choice preference situation, autistic children tended to prefer the more predictable mirror image to a previously taped film of self.
Genetic and ethanol‐related differences in maternal behavior and offspring viability in mice
Authors: Swanberg Karen M. , Wilson James R.
Published: January 2005

Primiparous female mice of 2 lines genetically selected for different narcotic responses to ethanol were administered 10% (v/v) ethanol in their drinking water during Days 2–14 of lactation. Ethanol treatment resulted in a marked decrease in growth and viability of pups in both lines. Fewer offspring of the ethanol‐sensitive line survived to weaning, apparently because of the failure of a large number of dams to exhibit maternal care. The combination of ethanol treatment and an additional environmental stressor (mouse hepatic virus) had a devastating effect on maternal behavior and offspring survival in the ethanol‐sensitive line, but far less effect on the ethanol‐insensitive mice. Thus, ethanol‐sensitive animals appear to be more susceptible to a variety of stressors, including ethanol.
Attachment and separation distress in the infant guinea pig
Authors: Pettijohn Terry F.
Published: January 2005

This study systematically examined separation‐induced distress vocalization in the infant guinea pig. Experiment I found that under maximum separation from both social and physical surroundings, the distress vocalization rate remained high for the 1st 4 weeks and then continuously declined to near zero by Week 12. Repeated testings had no effect on habituation of the rate during Week 5. Experiment II, using separation distress vocalization responses to the social (the mother) and the physical (the home pen) environments, showed that when the mother was present the vocalization rate was extremely low, and when she was absent the rate was moderate if the subject was isolated in the home box and high if the subject was in an unfamiliar box. Experiment III confirmed the finding that primary social attachment took place toward the mother. These results corroborate other attachment measures, and indicate the usefulness of the vocalization technique for the study of attachment in the infant guinea pig.
Mother‐infant separation in group‐living rhesus macaques: A hormonal analysis
Authors: Smotherman William P. , Hunt Lynn E. , McGinnis Lynda M. , Levine Seymour
Published: January 2005

Adrenocortical responsiveness to separation in group‐living rhesus macaque mother‐infant pairs was determined. Cortisol evaluations were complemented by behavioral observations of mother‐infant interactions and group social behavior. Infants, but not their mothers, showed cortisol elevations that could be attributed specifically to separation. Steroid‐behavior relationships suggested that the infants of high dominant mothers evinced the greatest adrenocortical response to separation. These data exemplify the complexities involved in determining endocrine/behavior relationships in a group‐living situation.
Ultrasounds and maternal behavior in the Mongolian gerbil
Authors: Elwood Robert W.
Published: January 2005

Female Mongolian gerbils were observed in undisturbed conditions and the ultrasounds produced by their pups were monitored. Ultrasound production was less in these conditions than with isolated pups. Correlations between various parameters suggest that nest‐building, sniffing pups, and licking pups are influenced primarily by ultrasounds whereas self‐grooming, feeding, and scratching are influenced primarily by the overall activity of the female.
Delayed plasticity of an instinct: Recognition and avoidance of 2 facing eyes by the jewel fish
Authors: Coss Richard G.
Published: January 2005

A model depicting 2 horizontally positioned black spots resembling facing eyes, as compared with models depicting other spot arrangements, elicits intense flight activity in young African jewel fish (Hemichromis bimaculatus) under 5 months of age and 7‐month‐old subadults reared apart from conspecifics with eyeless cave fish (Anoptichthys jordani). In contrast, subadults permitted to observe or interact fully with conspecifics during development exhibited attenuated discriminative flight activity. These findings suggest that visual experience with facing conspecifics, irrespective of physical contact, modifies the flight‐eliciting properties of the innate mechanism subserving eye‐schema recognition, but only during later maturation.
Social experience affects the development of dendritic spines and branches on tectal interneurons in the jewel fish
Authors: Coss Richard G. , Globus Albert
Published: January 2005

African jewel fish reared with eyeless cave fish, but without visual‐tactile contact with conspecifics, exhibit hyperresponsive behavior after release in community aquaria. Because the optic tectum might be affected by these restraints on visual experience, unreleased members of the same social isolate group were compared histologically with controls reared in community aquaria. Using the rapid Golgi method, we counted dendritic spines and branches on pyriform interneurons between 402 and 529 days of age. As compared with isolates, control group interneurons exhibited significantly more spines and primary branches on apical dendrites in deep tectal layers. Our focus is the relation between experiential differences in rearing conditions and synaptic changes in the deep tectal layers.
Behavioral and physiological effects of early handling and early malnutrition in rats
Authors: Cines Brenda M. , Winick Myron
Published: January 2005

This experiment employed a 2 × 2 design in which the nutritional and early stimulation conditions of rat pups were manipulated during the 1st 3 weeks of postnatal life. Animals were observed in various open field activities at 22, 23, 29, 36, and 50 days of age, and killed at 55 days of age for neurochemical analysis. Early handling decreased the behavioral differences due to malnutrition and resulted in fewer, but larger cells in rat forebrain for both well‐nourished and malnourished groups.
The effects of protein malnutrition on the behavior of rats during the suckling period
Authors: Hall Robert D. , Leahy J. Patrick , Robertson Wendy M.
Published: January 2005

Observations of 2 groups of dams and their litters were made every 3 hr around the clock on Days 1‐20 postpartum. The dams were fed either an 8% or a 25% casein diet for 5 weeks before mating and during gestation and lactation. Dams on the low protein diet spent more time in the nest actively nursing their young than did high protein dams, and they exhibited no deficits in other maternal behaviors. Five of 11 kinds of behavior developed more slowly in the undernourished pups than in the well‐nourished ones, but the developmental delays were no longer than a few days. Circadian fluctuations were apparent in all of the pups' activities during the 3rd postnatal week as well as in grooming and horizontal movement, 2 behaviors that were present earlier, by 6–10 days of age.
Long‐term effects of preweaning taurine injections in rats: Interactions with strain and gender
Authors: Valliant Paul M. , Persinger Michael A. , Satinder K. Paul
Published: January 2005

A comparison was made of MR, MNR, and RCA strains that had been injected with either 62.5 mg/kg of taurine or comparable volumes of physiological saline between postnatal Days 8 and 20 and later tested at 100 days of age in an open field and 1‐way shock avoidance situations. Taurine‐injected rats displayed significant elevation in defecation score in the open field. In addition a significant Treatment × Strain interaction was due to the larger defecation numbers displayed by the taurine‐injected MR rats relative to the saline‐injected MR rats.
Effects of urine from pregnant and lactating female house mice on sexual maturation of juvenile females
Authors: Drickamer Lee C. , Hoover John E.
Published: January 2005

The effects of urine from pregnant and lactating female mice on puberty in young females were examined. In Experiment I urine from pregnant or lactating females painted daily on the external nares of young females led to earlier sexual maturation than treatment with water or urine from singly‐caged, nonlactating, multiparous adult females. In Experiment II urine from either pregnant or lactating females, injected daily into perforated plastic capsules containing cotton, effected earlier maturation in female mice caged with these capsules than did the urine of singly‐caged females or water. In Experiment III the effectiveness of these treatments on reproduction per se was confirmed: young females reaching maturity earlier as the result of urine treatments were in fact ovulating and were capable of conceiving and bearing young. One explanation for the presence of the urinary pheromone(s) involves changes in hormone levels during pregnancy and/or lactation and urinary excretion levels of hormones, hormone metabolites, or chemical compounds which are hormone dependent. The pheromone excretion, triggered by external factors, may be a general signal to other females that environmental and/or social conditions are favorable for reproductive activities.
Developmental changes in the suckling behavior of hamster pups: A comparison with rat pups
Authors: Hall W. G. , Rosenblatt Jay S.
Published: January 2005

The suckling behavior of hamster pups was observed to undergo several transitions during the preweaning period. Pups 10 days of age and younger attached to the nipples of their anesthetized mothers and suckled. After 10 days of age, however, only animals which had been deprived of suckling (and food and water) reliably attached to their mothers' nipples. By 25 days of age, deprived pups no longer suckled. The pattern of response after nipple attachment also changed during development: pups younger than 5 days of age remained on 1 nipple after initial attachment, whereas older pups shifted from 1 nipple to another. The development of suckling in hamster pups resembles that in rat pups, although certain changes or transitions occur at different ages in the 2 species. These changes may provide important markers for neural and behavioral development in each species and for comparisons between the two.
Development of tonic immobility in the rabbit: Relation to body temperature
Authors: Whishaw Ian Q. , Flannigan Kelly P. , Barnsley Roger H.
Published: January 2005

Tonic immobility was studied in rabbit pups varying in age from 1 to 30 days. During the 1st 2 postnatal weeks the rabbits were active in an open field, had difficulty walking and executing a righting response, lost body temperature rapidly, and had no, or only short durations of, tonic immobility. After this age they were less active, hopped and righted well, maintained core temperature, and showed increased durations of tonic immobility. Within the 1st 2 postnatal weeks cooling and warming potentiated; thereafter, cooling disrupted and only warming potentiated tonic immobility. The results suggest that rate of heat loss can act as a stimulus to block tonic immobility and increase activity in neonatal rabbits. With development, cooling produces shivering which can disrupt tonic immobility, whereas warming may raise movement initiation thresholds which can potentiate tonic immobility.
The development of social structure during the primary socialization period in German shepherds
Authors: Wright John C.
Published: January 2005

The ontogeny of primary socialization in a litter of 5 German shepherd puppies was investigated using both arena tests and rearing environment (kennel) conditions. Tests for exploratory behavior, conducted at 5 1/2, 8 1/2, and 11 1/2 weeks of age, showed reversals in amount of exploration over the 6‐week period. Dominance was also investigated at 5 1/2, 8 1/2, and 11 1/2 weeks, using both a bone‐in‐pen test and a rearing environment setting. By comparison of the subjects' dominance scores at each age for both settings, evidence was found for the separation of the development of dominance behavior into 2 kinds: competitive and social dominance. The scores for exploratory behavior (stimulus reactivity) and competitive dominance were clearly related: those pups at 5 1/2, 8 1/2, and 11 1/2 weeks that were most exploratory also ranked highest for competitive dominance.
Acquisition and retention of multidirectional escape behavior in preweanling rats
Authors: Misanin James R. , Brownback Thomas , Shaughnessy Lynn D. , Hinderliter Charles F.
Published: January 2005

The shock‐escape behavior of preweanling rats in a multidirectional escape situation was examined in 3 experiments. In Experiment I, 5‐, 7‐, 9‐, and 11‐day‐old rats were given shock‐escape training on each of 3 days. Rats younger than 7 days of age did not improve escape responding within or over sessions. Animals 7 days of age and older, however, showed both an intrasession improvement and an intersession improvement that could not be attributed solely to maturation. In Experiment II, the escape behavior of 3‐, 5‐, and 7‐day‐olds was examined in an apparatus modified to take into account the poor locomotor abilities of these animals. They were given escape training on 3 successive days. Again, no within‐session improvement was found in rats under 7 days of age. However, an intersession improvement was found in rats whose training began at 5 days of age. This improvement was due to maturation and did not reflect a cumulative effect of training. Experiment III, like Experiment I, demonstrated that the intersession improvement in the older rats was not simply a maturation effect. It also demonstrated that the improvement could not be attributed to the stress of prior handling, shock, or body temperature loss, but was, rather, a retention effect. These results support the contention that the emergence of memory is task specific.
Development of between‐limb movement synchronization in the chick embryo
Authors: Provine Robert R.
Published: January 2005

Spontaneous between‐limb movement synchronization is described as the amount of concurrent limb movement observed in 7–‐19‐day chick embryos. At early stages, a wing moved as often with the ipsilateral leg as with the contralateral wing. Later, between‐girdle (ipsilateral wing‐leg) synchronization progressively decreased and within‐girdle (wing‐wing) synchronization increased, especially after 15–‐17 days. Bilaterally synchronized movements of the wings as in flapping and of the legs as in walking appeared at embryonic stages. Both wing and leg motility increased between 7 and 13 days and declined until hatching. The wings and legs were equally active except at 17 and 18 days when the wings moved more frequently than the legs. The left and right wings were equally active. These behavioral events reflect developmental changes in the motor outflow of the central nervous system.
A biobehavioral developmental profile (BDP) for the pigtailed monkey
Authors: Reite Martin , Short Robert
Published: January 2005

Behavioral development during the 1st 5 months of life was observed in 21 group‐living mother‐reared pigtailed (M. nernestrina) monkey infants. Periodic behavioral observation sessions provided monthly mean scores for 28 different behavioral items. Infants appeared to be separable on several behavioral continua, including their general level of activity and the nature of the mother‐infant relationship. Individual differences were prominent, appeared early and persisted. Patterns of behavior were examined and found to be stable across time.

Physiological data (heart rate, body temperature, sleep patterns EEG activity) were collected from 15 of the infants at a mean age of 23 weeks using totally implantable multichannel biotelemetry systems. Group mean values and measures of individual variability were obtained for 23 physiological variables. Physiological variables were correlated with each other and measures of concurrent behavior; the following relationships emerged:

Animals with higher body temperatures, both day and night, also tended to have higher heart rates.

EEG alpha frequency and alpha ratio (a measure of alpha organization) were positively correlated, meaning animals with higher‐frequency alpha activity tended to have better organized alpha, with less background slowing.

Animals with higher alpha frequencies and alpha ratios had more cardiac arrhythmias.

Animals with lower body temperatures had longer REM periods and had more Drowsy and less Stage 2 sleep periods, with more frequent awakenings.

More active animals had higher body temperatures and heart rates both day and night; animals who rested more had lower body temperatures.

Infants that spent more time away from the mother (not in physical contact) appeared to have more cardiac arrhythmias.

Infants that were carried more or cradled more by the mother tended to have lower alpha ratios (more slow activity intermixed).

More active infants tended to have more Stage 3 4 sleep, less REM sleep, and shorter REM periods than did less active infants.

The behavioral data collected during the 1st 4 months of life in the subset of 15 infants were correlated with the subsequent physiological data, and several different types of correlational patterns emerged. Certain physiological variables were highly correlated with behavior during all months, others were highly correlated only with early behavior (e.g., Months 2 and 3) or with lnter behavior (e.g., Months 3 and 4).
Prenatal influence of mild decompressions on hooded rats
Authors: Graessle Charles A.
Published: January 2005

Frequent, brief, and mild prenatal decompressions caused decreases in newborn rats' viability and in survivors' “emotional” development. Both hypoxia and otic barotrauma contributed to these effects, but hypoxia, alone, did not affect offspring behavior in the open field or in a shock avoidance task.
Acquisition and retention of classical conditioning in the newborn rat
Authors: Bachevalier Jocelyne , Blozovski Denise
Published: January 2005

The development of memory of a conditioned response was examined in London black rats between 0 and 4 days of age. For the conditioning, a vibrotactile stimulus paired with an electric shock was presented to the animal 80 times with an interval of 2000 msec between stimuli. The animals were retested at retention intervals of 3 min or 24 hr. The results showed that 0‐, 2‐, 3‐, and 4‐day‐old rats possess a retention capacity of at least 24 hr and suggest that the emergence of memory may be task‐specific.
Retained elements of early avoidance training and relearning of forgotten operants
Authors: Sussman Paul S. , Ferguson H. Bruce
Published: January 2005

In a series of 7 experiments we investigated the possibility that juvenile rats show long‐term retention for aspects of early avoidance training and that these retained elements serve to reinforce relearning of the forgotten operants. Rats trained in active or passive avoidance at 23–25 days of age demonstrated the typical juvenile forgetting effect relative to adults after a 28‐day interval. However, both juveniles and adults demonstrated marked reductions in locomotor activity prior to retraining which were specific to the apparatus and not dependent on the opportunity to perform an operant during initial training. Juvenile animals given a reminder exposure plus footshock 27 days after training, then single daily nonshock trials (Days 28–30), showed decreasing crossover latencies across days if trained in active avoidance and increasing latencies if trained in passive avoidance. This reappearance of task‐appropriate crossover latencies was evident in previously trained juveniles only. Finally, young animals' demonstrated change in crossover latency is associated with subsequent superior acquisition performance, and this change depends upon the presentation of the test trials for its appearance. We suggest that the amelioration of “infantile amnesia” associated with the present procedures is a learning process motivated by Pavlovian components of training which are retained well, by juveniles and adults alike, over intervals typical of ontogeny of memory research.
Models of infantile malnutrition in rats: Effects on maternal behavior
Authors: Crnic Linda S.
Published: January 2005

The effects of 6 commonly used methods for producing malnutrition in suckling rats upon the behavior of their dams were examined. In these methods, (1) large litters were fostered on the dams; (2) dams were fed low‐protein diets; (3) dams were fed an inadequate amount of a good quality diet; (4) pups were removed from the dams and kept with a nonlactating female for half of the day; (5) pups were removed from the dams and kept in an incubator for half of the day; or (6) some of the dams' teats were destroyed. Dams that were themselves food deprived showed a shift from resting to exploratory behaviors with some indication of increased attention to the pups compared to controls. Dams whose pups were starved but that were well fed themselves showed lower levels of resting and higher levels of attention to pups but no elevation in exploratory activity. Although the long‐term significance of the behavioral changes of the dams is not known, the immediate effect was to minimize the impact of the experimenter's manipulations on the metabolic energy available to the pups for growth and development.
Dietary influences on the development of sucrose acceptability in rats
Authors: Bertino Mary , Wehmer Francine
Published: January 2005

Weanling rats were placed on a high‐fat diet or chow. Beginning at 5 weeks of age, they were tested for acceptability of 4 sucrose solutions of different concentrations once a week until they showed the previously established adult pattern of acceptability. Subjects on the chow diet showed a gradual transition from a juvenile to adult pattern of acceptability, that is, a progressive downward shift in the concentration of solution that is most acceptable. Subjects on the high‐fat diets never showed the adult pattern but continued to display a juvenile pattern of acceptability throughout the experiment. The data obtained from the subjects on the high‐fat diets are similar to those on taste preferences in obese humans.