Thus, the big share

Thus, the big share of venous outflow from is referred, apparently, back to a brain on the vessels going along a leg of a pituitary body. The blood flow referred from a hypothalamus in a pituitary body, is a basis vorotno-vascular hypotheses of subthalamic regulation of functions of a forward share of a pituitary body (see chapter 6). The retrograde blood flow provides a probable way of short circuit of return hormonal communication of a forward pituitary body with a hypothalamus. The blood flow in a forward pituitary body levitra makes 0,8 ml/g in 1 mines that exceeds a blood flow in all tissues of mammals. The innervation of a forward pituitary body is extremely poor and presented almost exclusively by the postganglionic sympathetic fibers accompanying bifurcations of arterioles and terminating on blood vessels. However there are few proofs of change of rate of a blood flow in a pituitary body at changes of activity of sympathetic nervous system. Nervous communications between back and forward shares of a pituitary body though their function is unknown are described also. FETOLOGY
The analysis of an embryogenesis of a pituitary body in many respects promotes understanding of anatomic distribution in it of cells of a miscellaneous ooze, developments of various congenital anomalies, and also formations and growth directions tumours. The glandular part of a pituitary body - - is formed of pocket representing emboly of an ectoderm of the top department drinks which eventually is bridged to a protrusion of area of III ventricle of an intermediate brain of a developing embryos. This part of an intermediate brain is differentiated in a neurohypophysis or a back share of a pituitary body. That site of pocket which does not contact to an intermediate brain, is enlarged, forming a forward share of a pituitary body. order decadron At early stages of development two tissues from forward shares merge on an average line and extend along a pituitary body leg. At animal some kinds this structure named a part, forms a full cover surrounding a leg, but at the person it is limited by group of the cells which are settling down along forward area of a leg of a pituitary body. That part of pocket which immediately contacts to a neurohypophysis, develops less intensively, than the opposite wall of a pocket, and forms an intermediate share. At animal some kinds, for example at rats, this share and at mature age remains in the form of separate anatomic formation which is easy for distinguishing. At the person of a cell of an intermediate share are admixed with cells of a forward share and form the incorporated structure named a distal part. Cells of an intermediate share, developing, get ability to cosecrete Adrenocorticotrophinum (), a hormone (), and endorphines whereas cells of a forward share start to cosecrete a growth hormone (), Prolactinum, , (), luteinizing () and follicle-stimulating () hormones. Recently obtained at microsurgical excision of tumours of a pituitary body data testify that the embryogenesis of the cells involved in pathological process, in certain degree allows to expect localisation hormonal active tumours. At the person the cavity of pocket obliterates, being filled with a developing pituitary body. On neurohypophysis border the rests of this cavity in the form of a cleft or the small cysts filled with a colloid which at children are expressed more accurately, than at adults can remain. Already at very early stage of development growing of the mesenchyma forming the basic bone, breaks contact of pocket to a forward part of a pharynx. However even at adults in the basic bone or near to it some cells of the bottom part of a pocket which form a so-called pharyngeal pituitary body can remain. These cells contain secretory granules at which are present at least and Prolactinum, and is not excluded, that in the conditions of excision or destruction of a distal part the given structure can find out appreciable endocrine function. The bookmark of a pituitary body at a foetus of the person is taped for the first time on 4-5th week of pregnancy, and its cellular differentiation occurs very quickly; basphilic cells appear on 7th, and atsidofilnye th 9-10th week. The hypothalamus where on 13th week it is possible to observe fluorescence of monoamines in a median eminence is differentiated also, and the primary plexus of portal vessels soon develops. By 20th week gipotalamo-gipofizarnaja the axis looks already quite mature. Secretory granules in a foetus pituitary body managed to be observed already in the end of I trimester of pregnancy, and already on 7th week pituitary body hormones are defined.