Επίδραση του αδρενεργικού αποκλεισμού στην έκφραση του επιδερμιδικού αυξητικού παράγοντα (EGFr) στον προστάτη αδένα των επιμύων
Περίληψη
Ο προστάτης αδένας εξαρτάται από την ύπαρξη ανδρογόνων προκειμένου να αναπτυχθεί, να διαφοροποιηθεί και να διατηρήσει τη λειτουργικότητά του. Για τη βιολογική δράση των διαφόρων εξωγενών παραγόντων όπως οι ορμόνες ή άλλες ουσ
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Επίδραση του αδρενεργικού αποκλεισμού στην έκφραση του επιδερμιδικού αυξητικού παράγοντα (EGFr) στον προστάτη αδένα των επιμύων
Περίληψη
Ο προστάτης αδένας εξαρτάται από την ύπαρξη ανδρογόνων προκειμένου να αναπτυχθεί, να διαφοροποιηθεί και να διατηρήσει τη λειτουργικότητά του. Για τη βιολογική δράση των διαφόρων εξωγενών παραγόντων όπως οι ορμόνες ή άλλες ουσ
Αρχική
![]() Περίληψη σε άλλη γλώσσαThe prostate gland is androgen dependant for his growth, differentiation and functional homeostasis. The biological effects of extrinsic factors such as hormones and other endocrine related agents are mediated by various peptide growth factors which are produced by the prostate gland and influence prostate function by promoting inter- and intracellular signalling between and within cell populations and also regulate the relationship between stromal and epithelial cells. The actions of peptide growth factors are androgen-dependant and androgen- independant and manage to regulate the increase of cell populations through receptors of cellular surface, which activate complicated pathways of signal transportation. Their combined function in prostate gland has as a result, either its normal growth or the creation of pathological entities: benign prostatic hyperplasia and prostate cancer.Sympathetic nerves and catecholamines, apart from the smooth muscle fibers ς ΚΥΠ.Με δεδομένο ότι ο EGF παίζει κυριαρχικό ρόλο τόσο στην έναρξη όσο και στην περαιτέρω επιδείνωσης της υπερπλασίας του αδένα, είναι πιθανόν ότι η αναστολή της έκφρασης του υποδοχέα του με αυτές τις φαρμακευτικές ουσίες να αναστείλει ή να καθυστερήσει την εμφάνιση ή περαιτέρω επιδείνωση της ΚΥΠ.Τα δεδομένα της μελέτης αυτής βοηθούν στην περαιτέρω θεμελίωση της άποψης ότι η τροποποίηση της δράσης του αυτόνομου νευρικού συστήματος στον προστάτη αδένα δεν έχει σα μόνο αποτέλεσμα τη μεταβολή της συσπαστικότητας των λείων μυϊκών ινών, αλλά ότι μεταβάλλει και τη διαδικασία ανάπτυξής του.Επιπλέον αποδεικνύεται, για πρώτη φορά στην διεθνή βιβλιογραφία, ότι η αναστολή της ενεργοποίησης τόσο των α όσο και των β- αδρενεργικών υποδοχέων έχει σαν αποτέλεσμα τη μεταβολή της διακυττάριας επικοινωνίας, μέσω των πεπτιδικών αυξητικών παραγόντων.
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Περίληψη σε άλλη γλώσσαThe prostate gland is androgen dependant for his growth, differentiation and functional homeostasis. The biological effects of extrinsic factors such as hormones and other endocrine related agents are mediated by various peptide growth factors which are produced by the prostate gland and influence prostate function by promoting inter- and intracellular signalling between and within cell populations and also regulate the relationship between stromal and epithelial cells. The actions of peptide growth factors are androgen-dependant and androgen- independant and manage to regulate the increase of cell populations through receptors of cellular surface, which activate complicated pathways of signal transportation. Their combined function in prostate gland has as a result, either its normal growth or the creation of pathological entities: benign prostatic hyperplasia and prostate cancer.Sympathetic nerves and catecholamines, apart from the smooth muscle fibers tone regulation, influence also ...
The prostate gland is androgen dependant for his growth, differentiation and functional homeostasis. The biological effects of extrinsic factors such as hormones and other endocrine related agents are mediated by various peptide growth factors which are produced by the prostate gland and influence prostate function by promoting inter- and intracellular signalling between and within cell populations and also regulate the relationship between stromal and epithelial cells. The actions of peptide growth factors are androgen-dependant and androgen- independant and manage to regulate the increase of cell populations through receptors of cellular surface, which activate complicated pathways of signal transportation. Their combined function in prostate gland has as a result, either its normal growth or the creation of pathological entities: benign prostatic hyperplasia and prostate cancer.Sympathetic nerves and catecholamines, apart from the smooth muscle fibers tone regulation, influence also the growth of the smooth muscle cells, probably through the intermediate action of peptide growth factors. They act on smooth muscle cells via a dense network of adrenergic fibers by stimulating adrenergic receptors. In the same time current findings support that there is an endogenous autonomic nervous system hyperactivity in patients with benign prostatic hyperplasia and may have important implications concerning the pathophysiological mechanisms underlying or influencing benign prostatic hyperplasiaAn especially significant peptide growth factor is the Epidermal Growth factor -EGF, whose role is essential for the structural morphology of the adult prostate gland. Its production in the ventral prostate of rats is androgen-dependant. On the contrary, the expression of its receptor (EGFr) is androgen-independant. The placement of EGFr in the basal/endocrinic cells and the expression of EGF of the secretai epithelial cells in combination with the fact that the secretion of EGF is under the control of autonomic nervous system, support the hypothesis that there is paracrinie communication between the basal and secretai cells.The present study was designed to assess the alteration of EGFr expression in the rat ventral prostate in response to adrenoreceptor blockade.Forty 100-days-old male Wistar rats were separated into two groups of twenty rats each. Ten animals of the first group were given per os terazocin (1,2 mg/kg for 4 months), while the other 10 animals of the same group were given normal saline. Ten animals of the second group were given propranolol (100mg/kg/day for 3 months), while the other 10 animals of the same group served as controls.The animal group that was given terazocin presented significant differences in EGFr expression. Its expression was significantly decreased or totally absent. The propranolol animal group also presented significant differences in EGFr expression. Its expression in this group was also decreased. The decrease in receptor’s expression may reflect the fact that either its production or its bioavailability is under adrenergic control. Anyway, receptor’s expression decrease after adrenergic blockade results in inability of connection and function of any previously connectable factor, a reaction that is known to be necessary for the balanced TGFß activity and the unaffected morphology of the gland. The unchanged remaining expression of EGFr in mastcells after al-AR blockade with terazocin is also interesting because suggests the indépendance of this cell population of ANS at least in whatever concerns the PGF signal transforming system. This finding with the combination of the fact that we did not observe any morphological changes of the prostate gland after a- or β- adrenergic blockade is driving to the hypothesis that gland’s homeostasis is preserved thanks to more than one control and protection systems.In conclusion, long-term administration of terazocin or propranolol can affect the natural history of BPH. EGF is known to play a significant role in inducing and further enhancing gland’s hyperplasia. We suggest that its receptor’s expression blockade with these pharmaceutical agents can inhibit or delay the presentation or further deterioration of BPH.Our findings further confirm the suggestion, that ANS functions can affect not only the contraction of prostatic smooth muscle fibers but also the gland’s growth project. It is also proved for the first time, to our knowledge, that the blockade of activation of the a and ß - AR, results in significant changes in transcellular communication, which is determined by the peptide growth factors.
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