CONTEXT: In the experimental animal, inflammatory signals quench LH's feedforward drive of @entity251 (T) secretion and appear to impair GnRH-LH output. The degree to which such suppressive effects operate in the @entity1 is not known. OBJECTIVE: To test the hypothesis that @entity1199 impairs LH's feedforward drive on T and T's feedback inhibition of LH secretion in healthy @entity1 . SETTING: Mayo Center for Translational Science Activities. @entity1 OR OTHER @entity1 : A total of 35 healthy @entity1 , 17 young and 18 older. INTERVENTIONS: Randomized prospective double-blind saline-controlled study of @entity1199 infusion in 2 doses with concurrent 10-minute blood sampling for 24 hours. MAIN OUTCOME MEASURES: Deconvolution analysis of LH and T secretion. RESULTS: After saline injection, older compared with young @entity1 exhibited reduced LH feedforward drive on T secretion (P < .001), and decreased T feedback inhibition of LH secretion (P < .01). After @entity1199 injection, LH's feedforward onto T secretion declined markedly especially in young subjects (P < .001). Concomitantly, @entity1199 potentiated T's proportional feedback on LH secretion especially in older volunteers. CONCLUSION: This investigation confirms combined feedforward and feedback deficits in older relative to young @entity1 given saline and demonstrates 1) joint mechanisms by which @entity1199 enforces biochemical @entity6126 , viz, combined feedforward block and feedback amplification; and 2) unequal absolute inhibition of T and LH secretion by @entity1199 in young and older @entity1 . These outcomes establish that the male @entity444 is susceptible to dual-site suppression by a prototypic inflammatory mediator. Thus, we postulate that selected ILs might also enforce @entity14136 in @entity32 .

Proinflammatory Cytokine Infusion Attenuates LH's Feedforward on XXXX Secretion: Modulation by Age.

@entity1 :: ('9606', 'Species') :: ['human', 'PATIENTS', 'PARTICIPANTS', 'men'] @entity32 :: ('MESH:D007249', 'Disease') :: ['chronic systemic inflammation'] @entity251 :: ('MESH:D013739', 'Chemical') :: ['testosterone'] @entity6126 :: ('MESH:D007006', 'Disease') :: ['hypogonadism'] @entity1199 :: ('3558', 'Gene') :: ['IL-2'] @entity444 :: ('MESH:D006059', 'Disease') :: ['gonadal axis'] @entity14136 :: ('MESH:D005058', 'Disease') :: ['male hypogonadism']
@entity251 :: (MESH:D013739,Chemical) :: ['Testosterone']
