Nerve growth factor immunoreactivity in the anterior pituitary of the rat.

Nerve growth factor (NGF) has long been recognized for its neurotrophic actions upon sensory and sympathetic neurons of the PNS and upon cholinergic neurons of the CNS basal forebrain. Much evidence, however, suggests that potential reciprocal interactions between NGF and various endocrine systems may also occur. In the present investigation we used immunohistochemical techniques to investigate whether NGF is found within the adult rat pituitary, thereby suggesting a possible interaction within this critical neuroendocrine gland. Our results indicate that NGF immunoreactivity is present only within the anterior lobe of the male and female rat pituitary and is exclusively localized within cells immunoreactive for thyroid stimulating hormone (TSH).