Endocrine Abstracts

Complement C5a is associated with various pro-inflammatory effects such as chemotaxis, production of superoxides, histamine release, vasodilatation and smooth muscle contraction. In sepsis, excessive production of C5a can lead to multi-organ failure. C5a mediates its actions through the C5a receptor (C5aR) but may also bind to a second receptor called C5L2 that acts as a decoy for removing excess C5a. C5a is also rapidly cleaved to a less active form, C5adesR; C5L2, in contras...

The hypothalamic-pituitary-adrenal axis is a major regulation of inflammation via the release of adrenal glucocorticoids. We recently showed that anaphylatoxin C3a receptors are expressed throughout the anterior pituitary gland and that immune-derived complement C3a and its less active derivative, C3adesR (loss of C-terminal arginine) are potent stimuli for pituitary hormones.In this study we investigated the expression of the anaphylatoxin receptor C5a ...

The hypothalamic pituitary adrenal (HPA) axis is the major regulator of stress and inflammation via the secretion of anti-inflammatory corticosteroids. This suggests an important bidirectional flow of information between the endocrine and immune systems. A critical component of the inflammatory response is the complement cascade in which anaphylatoxins C3a, C4a and C5a are released.In this report we used colocalisation immunohistochemistry to show detai...

We previously showed that adenosine stimulates IL-6 secretion from TtT/GF cells suggesting that adenosine is an important regulator of folliculostellate (FS) cell function. Gap-junction communication is also important for FS cell function so the aim of this study was to investigate the action of adenosine on connexin 43 (Cx 43) expression and intercellular communication.Adenosine production, as measured by reverse-phase fluorescent HPLC, was easily detec...

The nucleoside adenosine is an important regulator of interleukin-6 secretion from the folliculostellate (FS) cells of the anterior pituitary gland but the source of adenosine in this scenario is unknown. Therefore the aim of this study was to investigate secretion of adenosine and the expression of adenosine forming and metabolising enzymes in the pituitary gland.Ecto-5/-nucleotidase (CD73), adenosine kinase and adenosine deaminase (AD) were ...

Folliculostellate (FS) cells form a three-dimensional network within the anterior pituitary gland and play a key role in regulating the endocrine response to inflammation and anoxic stress. Adenosine, released under such conditions in high concentration, modulates a number of inflammatory processes and can regulate the activity of the hypothalamic-pituitary-adrenal (HPA) axis. The identities of the adenosine receptor (AR) subtypes mediating these responses, however, and the si...