Unrelated peptide immunoreactivities coexist in neurons of the rat lateral dorsal hypothalamus: human growth hormone-releasing factor1-37-, salmon melanin-concentrating hormone- and alpha-melanotropin-like substances.

Antisera raised against 3 unrelated synthetic neuropeptides - salmon melanin-concentrating hormone, human growth hormone-releasing factor1-37, and alpha-melanotropin - stained the same extensive neuron population in lateral and dorsal areas of the posterior hypothalamus. Controls for specificity have shown that these 3 antisera bind 3 different epitopes. Differences in intracellular staining patterns suggest that these epitopes could be borne by distinct peptides.