title: Effects of naltrexone on energy- and palatability-driven consumption and neuronal activation in feeding-related forebrain areas: relationship with age

authors: McColl, Laura Kathryn

abstract: Intake of energy as well as interest in palatable foods diminish during the ageing process. One of the likely reasons underlying this phenomenon is an age-related decrease in the opioid tone in the brain. To further substantiate this hypothesis, the current project was aimed to elucidate the effects of an opioid receptor antagonist, naltrexone, on energy- and palatability-driven consumption in 6-, 16- and 22-month old mice and on the activation of feeding-related forebrain circuitry (hypothalamic and accumbal) in adult vs old male mice. The findings indicate that old (22-month old) mice exhibit diminished responsiveness to anorexigenic properties of naltrexone in deprivation-induced intake of “bland” chow and eating for reward (consumption of low-/non-calorie solutions containing sucrose and saccharin). Interestingly, in the pilot studies performed in rats, sensitivity to anorexigenic action of naltrexone was similar at two different phases of adult lifespan prior to reaching the old age (2 months and 18months). The c-Fos immunoreactivity analysis in mice indicated that unlike in adult animals at a younger age, in old animals, naltrexone fails to activate the nucleus accumbens shell, the ventromedial and hypothalamic nuclei, and it activates the lateral hypothalamus. These c-Fos data provide an insight into neural responsiveness changes that might underscore differential feeding regulatory outcomes seen after naltrexone administration in old animals compared to their adult yet younger counterparts.

text: Effects of naltrexone on energy- and palatability-driven consumption and neuronal activation in feeding-related forebrain areas: relationship with age Intake of energy as well as interest in palatable foods diminish during the ageing process. One of the likely reasons underlying this phenomenon is an age-related decrease in the opioid tone in the brain. To further substantiate this hypothesis, the current project was aimed to elucidate the effects of an opioid receptor antagonist, naltrexone, on energy- and palatability-driven consumption in 6-, 16- and 22-month old mice and on the activation of feeding-related forebrain circuitry (hypothalamic and accumbal) in adult vs old male mice. The findings indicate that old (22-month old) mice exhibit diminished responsiveness to anorexigenic properties of naltrexone in deprivation-induced intake of “bland” chow and eating for reward (consumption of low-/non-calorie solutions containing sucrose and saccharin). Interestingly, in the pilot studies performed in rats, sensitivity to anorexigenic action of naltrexone was similar at two different phases of adult lifespan prior to reaching the old age (2 months and 18months). The c-Fos immunoreactivity analysis in mice indicated that unlike in adult animals at a younger age, in old animals, naltrexone fails to activate the nucleus accumbens shell, the ventromedial and hypothalamic nuclei, and it activates the lateral hypothalamus. These c-Fos data provide an insight into neural responsiveness changes that might underscore differential feeding regulatory outcomes seen after naltrexone administration in old animals compared to their adult yet younger counterparts.

year: 2017

title: Are geothermal streams important sites of nutrient uptake in an agricultural and urbanising landscape (Rotorua, New Zealand)?

authors: Hoellein, Timothy

subjects: ecosystem function

abstract: Increased nutrient loading and eutrophication are common problems for lakes globally (Carpenter et al., 1998; Smith & Schindler, 2009). New Zealand is no exception, where 30% of lakes >1 ha have very poor to extremely poor water quality (Van Bunnik et al., 2007). Many of the iconic lakes in the well-known, geothermally active Rotorua region of New Zealand exhibit the adverse affects of eutrophication, including harmful algal blooms, bottom water hypoxia, reduced clarity (Hamilton et al., 2010) and loss of aquatic biodiversity (Hamilton, 2004; Burns, Mcintosh & Scholes, 2009). These lakes are important to New Zealand both economically and culturally (Edgar, 2009).

text: Are geothermal streams important sites of nutrient uptake in an agricultural and urbanising landscape (Rotorua, New Zealand)? Increased nutrient loading and eutrophication are common problems for lakes globally (Carpenter et al., 1998; Smith & Schindler, 2009). New Zealand is no exception, where 30% of lakes >1 ha have very poor to extremely poor water quality (Van Bunnik et al., 2007). Many of the iconic lakes in the well-known, geothermally active Rotorua region of New Zealand exhibit the adverse affects of eutrophication, including harmful algal blooms, bottom water hypoxia, reduced clarity (Hamilton et al., 2010) and loss of aquatic biodiversity (Hamilton, 2004; Burns, Mcintosh & Scholes, 2009). These lakes are important to New Zealand both economically and culturally (Edgar, 2009).

year: 2012-01

title: Maori perspectives of the environment: Summary document

authors: Whangapirita, Laura

subjects: Maori

abstract: The Community and Economy Programme at Environment Waikato has developed a partnership with the Maori and Psychology Research Unit of the University of Waikato to further assist in strengthening its commitment to cultural research and information work. This relationship facilitated the development of the Maori and Environment project, which was conducted in two stages and produced a number of significant research reports throughout 2003. This is the summary document.

text: Maori perspectives of the environment: Summary document The Community and Economy Programme at Environment Waikato has developed a partnership with the Maori and Psychology Research Unit of the University of Waikato to further assist in strengthening its commitment to cultural research and information work. This relationship facilitated the development of the Maori and Environment project, which was conducted in two stages and produced a number of significant research reports throughout 2003. This is the summary document.

year: 2003-12