Neurogenesis of oxytocin-containing neurons in the paraventricular nucleus (PVN) of the female pig in 3 reproductive states: puberty gilts, adult gilts and lactating sows.

Evidence suggests that neurogenesis occurs in the adult hypothalamus, including centers containing oxytocin and vasopressin producing neurons. The present study was undertaken to look at one of these centers, the paraventricular nucleus (PVN), to describe its morphology, confirm the presence of neurogenesis and examine the effect of reproductive status on the incidence of neurogenesis. Serial sections of the paraffin-embedded hypothalamus were made from five puberty gilts, four adult gilts and four lactating sows.

The use of proliferating cell nuclear antigen immunohistochemistry with a unique functional marker to detect postnatal neurogenesis in paraffin-embedded sections of the mature pig brain.

Until recently, evidence supporting postnatal neurogenesis was controversial. Much of the debate has centered on the identification of the dividing cells as neurons versus glia. Because neurogenesis has become a well-documented phenomenon, there is a need for reliable protocols to identify recently divided neurons in a wide range of situations.

Postnatal neurogenesis in the vasopressin and oxytocin-containing nucleus of the pig hypothalamus.

The vasopressin and oxytocin-containing nucleus (VON) of the pig hypothalamus demonstrates dramatic postnatal growth in nucleus size, both volume and neuron number, during puberty, and continues to increase in size in the adult sexually mature female pig throughout its reproductive prime. This study was designed to show that postnatal neurogenesis is responsible for the VON growth that occurs between adolescence and maturity. Recently divided neurosecretory cells of the hypothalamus were identified in adolescent and mature non-lactating female pigs using a sequential immunohistochemistry double-labeling technique with monoclonal mouse antibodies to detect vasopressin and proliferating cell nuclear antigen (PCNA), a protein associated with the S phase of the cell cycle.