An electron microscopic immunocytochemical study on the tyrosine hydroxylase-positive, dopamine Beta-hydroxylase-negative cells in the pineal gland of golden hamsters.

Abstract We have examined the ultrastructure of tyrosine hydroxylase-positive, dopamine beta-hydroxylase-negative neuron-like cells in the pineal gland of golden hamsters by electron microscopic immunocytochemistry using antiserum to tyrosine hydroxylase. The tyrosine hydroxylase-positive cells were scattered throughout the parenchyma of the pineal gland. Their cell bodies were oval or spindle-shaped (maximum diameter 15 to 20 mum) with one or two short cell processes and a large round nucleus. They contained mitochondria, short rough-surfaced endoplasmic reticulum, Golgi apparatus, and granulated vesicles (50 to 100 nm). The cell membrane was in close contact with the pinealocyte cell body, pinealocyte processes and tyrosine hydroxylase-negative or -positive nerve terminals.