Bird CR also for production and stress pathway

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Hi All,

Here, is a paper that is not pdf-available and may suggest that CR in birds, as

in

non-human primates, has results on reproduction and stress pathways.

Since:

" reduced norepinephrine in key hypothalamic regions and reduced dopamine "

was seen, it may be relevent to define that:

" hypothalamus: A portion of the brain which lies beneath the thalamus and

secretes

substances which control metabolism by exerting an influence on pituitary gland

function. The hypothalamus is also involved in the regulation of body

temperature,

water balance, blood sugar and fat metabolism. The hypothalamus also regulates

other

glands such as the ovaries, parathyroids and thyroid " .

Now, here is the Medline abstract excerpt.

Ottinger MA, Mobarak M, Abdelnabi M, Roth G, Proudman J, Ingram DK.

Effects of calorie restriction on reproductive and adrenal systems in Japanese

quail: Are responses similar to mammals, particularly primates?

Mech Ageing Dev. 2005 May 31; [Epub ahead of print]

PMID: 15935442

.... Male Japanese quail were pair fed at 0% ad libitum (AL), 20%, or 40% CR of

AL,

recorded for juveniles (3-7 weeks of age) or adults (12-16 weeks of age).

Juvenile

males on CR matured more slowly, and both juvenile and adult males had reduced

plasma luteinizing hormone (LH) with CR. Adults on 40% CR showed evidence of

stress,

with increased plasma corticosterone and reduced testes weight and circulating

androgens. In a separate study, pituitary gland response was tested in juvenile

and

adult castrated males that had been on the same CR treatments. All birds

responded

to gonadotropin releasing hormone (GnRH) challenge, with LH release. However,

the

40% CR juvenile and adult birds had quantitatively lower responses, suggesting

central inhibition of the reproductive axis. This hypothesis was tested by

measurement of sexual behavior and catecholamines known to stimulate GnRH in

hypothalamic regions that modulate these responses. Results showed reduced

norepinephrine in key hypothalamic regions and reduced dopamine in posterior

hypothalamus. These data support the hypothesis that CR affects reproductive

function, with evidence for effects in the central nervous system. These data

are

discussed and compared to data collected in mammals, especially the rhesus

monkey,

on the effects of timing and degree of CR on reproductive and stress responses.

Al Pater, PhD; email: old542000@...

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