Distribution of immunoreactive prolactin cells in the pituitary of adult common carp, cyprinus carpio

Abstract EN

The distribution of prolactin-immunoreactive (PRL-ir) cells in the adenohypophysis of the common carp (Cyprinus carpio) was examined immunocytochemically using the avidin-biotin-peroxidase complex (ABC) method.

Two types of antisera were used mammalian antisera (rabbit anti-mice RRL) and fish antisera (rabbit anti-goldfish PRL).

Adult male carp were collected from control pond at Osaka Prefecture, Japan ; that covering the different breeding seasons.

The carp pituitary consists of the adenohypophysis and neurohypophysis ; the latter penetrated into the former to form complex interdigitations.

The adenohypophysis is further divided into three regions : rostral pars distalis (RPD), proximal pars distalis (PPD), and the pars intermedia (PI).

While the teleostean antisera showed specific immunoreaction with PRL cells in the carp adenohypophysis in the form of thick strands, clustered and/or follicles, there was no cross-reaction with that of anti-mice PRL.

The distribution of PRL-ir cells in C.

carpio was restricted to the area of the RPD, also in isolated or solitary clustered cells in the PPD, non in the PI.

The PRL-ir cells were triangular, polyhedral or spindle shape with centrally located, large spherical nucleus.

This is the first report to clarify the immunocytoch-emical identification and distribution of PRL cells in the common carp, C.

carpio, pituitary gland.