DISTRIBUTION OF MELANIN-CONCENTRATING HORMONE (MCH)-LIKE IMMUNOREACTIVITY IN NEURONS OF THE DIENCEPHALON OF SHEEP

An immunohistochemical study with an antiserum raised against salmon m elanin concentrating-hormone has demonstrated the presence of numerous melanin concentrating-hormone-immunoreactive neurons in the lateral h ypothalamic areas of the sheep. The pattern of distribution of these p erikarya is similar to that of rodents and primates. In sheep, however , melanin concentrating-hormone-immunoreactive neurons appeared to for m two gatherings: the first is situated ventromedially to the internal capsule and the second in the dorsolateral hypothalamus. In these are as, numerous immunostained perikarya are observed. Compared to the rat s, labelled neurons extended more caudally in the ventral tegmental ar ea and more rostrally above the optic chiasma. Compared to primates, t hese neurons are less numerous in the periventricular area. In our stu dy, dense networks of melanin concentrating-hormone-immunoreactive var icose fibers were observed in the supramamillary nucleus, the lateral hypothalamus, the nucleus medialis thalami and nucleus reuniens and in the bed nucleus of the stria terminalis. Copyright (C) 1996 Elsevier Science B.V.