An immunohistochemical study of temperature-related changes in galanin and nitric oxide synthase immunoreactivity in the hypothalamus of the toad.
Galanin (GAL) and nitric oxide synthase (NOS) have been implicated in the control of thermogenesis in mammals. An experimental protocol was designed to determine whether or not the expression of these molecules in the hypothalamus of the toad could be related to environmental temperature changes. Exposure of the animals to low temperature increased the number and intensity of NOS-positive neurons in the magnocellular hypothalamic region, in contrast to a weak immunoreactivity observed in control animals kept in a natural environment at a spring-summer temperature (23-27 degrees C). Also a significantly higher number of GAL-immunoreactive (-IR) cells was observed in the preoptic area as compared to that observed in controls, while no difference in the intensity of GAL immunostaining intensity was detected. These results show a temperature-related expression of GAL and NOS in the hypothalamus and preoptic area of the toad. The results suggest a possible role of GAL and NOS in the regulation of hibernation in these animals.
González Nicolini
M V
MV
Instituto de Neurobiología, Buenos Aires, Argentina.
Orezzoli
A A
AA
Villar
M J
MJ
D000064:Acclimatization / Q000502:physiology*; D000818:Animals; D002022:Bufo arenarum / Q000378:metabolism*; D002452:Cell Count; D019004:Galanin / Q000378:metabolism*; D007031:Hypothalamus / Q000166:cytology / Q000201:enzymology / Q000378:metabolism*; D007150:Immunohistochemistry; D008297:Male; D019001:Nitric Oxide Synthase / Q000378:metabolism*; D013696:Temperature
D019004:Galanin; D019001:Nitric Oxide Synthase