They also found that these stem cells are different from the majority of adult stem cells that trigger the initial growth of this important organ, reports ANI.

The results of the study also suggest a novel way that can be taken up by the pituitary gland in both adolescents and adults, to traumatic stress or to normal life changes like pregnancy. Earlier, Grigori Enikolopov, Ph.D., an associate professor at Cold Spring Harbour Laboratory (CSHL), had known that a gene called Nestin was active in neural stem cells and they had genetically engineered mice so that the same conditions that activate Nestin in a particular cell, also make it glow green under ultraviolet light. After that many such teams have used these special mice to help find adult stem cells in hair follicles, liver, muscle, and other tissues. The pituitary gland in humans is about the size of a pea and sits at the base of the brain, where it secretes hormones that regulate various processes throughout the body. However, in mice, the gland develops in the embryo, but then has a second growth spurt.

Anatoli Gleiberman, Ph.D., a researcher in the laboratory of pituitary expert M. Geoff Rosenfeld at the University of California, San Diego, in collaboration with Grigori Enikolopov, aimed to look for pituitary stem cells. They used the Nestin-tracking mice to identify candidate cells in the anterior pituitary, the section of the organ that secretes hormones and later they used other techniques to show that these are true stem cells. Enikolopov said, "There are six main lineages in the adult pituitary and we can demonstrate that one adult stem cell can generate all six lineages," with each cell type secreting a different hormone. However, these cells differ from most adult stem cells.

The researchers showed that adult stem cells in the pituitary did not help construct the embryonic organ. They suggested that their research indicates that the adult mouse pituitary includes two similar, but not identical, types of hormone-producing cells: some that grew in the developing embryo, and some that appeared later. They even hypothesised that having two sets of cells may let the organ respond differently to changing body conditions. Dr Enikolopov mentioned that hormones strongly influence human neuropsychiatric phenomena, including stress and depression that are his main research focus. The study, titled, ‘Genetic approaches identify adult pituitary stem cells’ appeared in a recent edition of the Proceedings of the National Academy of Sciences.