TY - JOUR
T1 - Effects of short-term cold exposure on pineal biosynthetic function in rats
AU - Tannenbaum, Michael G.
AU - Reiter, Russel J.
AU - Vaughan, Mary K.
AU - Troiani, Maureen E.
AU - Gonzalez-Brito, Aldo
N1 - Funding Information:
This work was supported by NSF Grant PCM 8410592to R.J.R. and a Marshall University Foundation Grant to M.G.T. A portion of this research was presenteda t the 1986A nnual Meeting of the American Society of Zoologists. The authors thank Valentina Golovko, E. Bowie Kahle, Margaret Rifleman, and Annette Smith for technical assistance.T wo anonymous reviewers kindly read and offered constructive criticism on an earlier draft of this paper.
PY - 1988/6
Y1 - 1988/6
N2 - In light of recent studies demonstrating stress-induced changes in pineal indoleamine metabolism, we tested the effect of acute cold stress on pineal biosynthetic function. Adult male rats were subjected to 30, 60, or 120 min of cold exposure (Ta = 2 °C) during either the light or dark phase of the daily photoperiodic cycle. Controls were kept at room temperature (22 ± 2 °C). Animals were killed by decapitation and pineals were analyzed by radioimmunoassay for melatonin content and by radioenzymeassay for the activity of N-acetyltransferase (NAT). Cold exposure during the day elicited no significant changes in pineal indoleamine metabolism. Exposure to cold for 1 hr during the second hour after lights off slightly increased pineal melatonin content, without a concomitant change in NAT activity. Rats exposed to 2 hr of cold beginning 2 hr after lights off, however, displayed a 50% reduction in NAT activity, whereas pineal melatonin content remained unchanged. The paradoxical response of pineal NAT activity and melatonin content are not uncommon when rats are exposed to adverse stimuli.
AB - In light of recent studies demonstrating stress-induced changes in pineal indoleamine metabolism, we tested the effect of acute cold stress on pineal biosynthetic function. Adult male rats were subjected to 30, 60, or 120 min of cold exposure (Ta = 2 °C) during either the light or dark phase of the daily photoperiodic cycle. Controls were kept at room temperature (22 ± 2 °C). Animals were killed by decapitation and pineals were analyzed by radioimmunoassay for melatonin content and by radioenzymeassay for the activity of N-acetyltransferase (NAT). Cold exposure during the day elicited no significant changes in pineal indoleamine metabolism. Exposure to cold for 1 hr during the second hour after lights off slightly increased pineal melatonin content, without a concomitant change in NAT activity. Rats exposed to 2 hr of cold beginning 2 hr after lights off, however, displayed a 50% reduction in NAT activity, whereas pineal melatonin content remained unchanged. The paradoxical response of pineal NAT activity and melatonin content are not uncommon when rats are exposed to adverse stimuli.
UR - http://www.scopus.com/inward/record.url?scp=0023945780&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0023945780&partnerID=8YFLogxK
U2 - 10.1016/0011-2240(88)90029-6
DO - 10.1016/0011-2240(88)90029-6
M3 - Article
C2 - 3396386
AN - SCOPUS:0023945780
VL - 25
SP - 227
EP - 232
JO - Cryobiology
JF - Cryobiology
SN - 0011-2240
IS - 3
ER -