Cau 26: cac hormon thuuy sau tuyen yen: ban chat, tac dung, dieu hoa bai tiet va UDLS
Hai hormon dc bai tiet tu thuy sau tuyen yen co nguon goc tu vung duoi doi. Chung dc bai tiet tu cac noron ma than khu tru o nhan canh n•o that va nhan tren thi. Sau khi dc tong hop chung dc vc doc theo soi truc den chua o cac boc nho nam trong tan cung TK khu tru o thuy sau tuyen yen. hai hormon do la hormon oxytocin va ADH
*) Hormon ADH
- ban chat hoa hoc: ADH hay con goi la vasopressin la 1 peptid co 9 acid amin
- tac dung:
+ voi 1 lg nho chi 2ng ADH khi tiem cho nguoi se lam giam bai tiet nc tieu do ADH co td lam tang taI hap thu nc o ong luon xa va ong gop. Nuu ko co ADH, ong gop va ong luon xa hau nhu ko taI hap thu nc lam cho 1 lg lon nc mat dI qua dg nc tieu. Ngc lai, voi su co mat cua ADH tinh tham nc cua ong luon xa va ong gop tang len nhieu lan, nc dc taI hap thu tro lai co the lam cho nc tieu dc co dac
+ voi Cm cao, ADH co td lam co mach cac tieu DM o toan co the do do lam tang huyet ap. chinh vi ly do nay ma ADH con co ten thu 2 la vasopressin
- Dieu hoa bai tiet:
+ dieu hoa = ap suat tham thau: khi dich the dam dac (ap suat tham thau tang), nhan tren thi bi kick thick, cac tin hieu kick thick se chuyen den thuy sau tuyen yen va gay bai tiet ADH. ADH dc mau dua den TB lam tang tinh tham dvoi nc cua TB ong than db ong gop do vay hau het nc taI hap thu trong khi cac chat dien giaI van tiep tuc dua ra nc tieu do do nc tieu dc co dac.
+ dieu hoa = the tick mau: the tick mau giam la 1 tac nhan manh gay bai tiet ADH. Tac dung nay db manh khi the tick mau giam tu 15 - 25%, khi do nong do ADH co the tang toi 50 lan cao hon binh thg.
*) Oxytocin
- ban chat hoa hoc: oxytocin cung la 1 peptid co 9 acid amin, chi co a.a thu 8 khac voi ptu ADH
- tac dung:
+ tac dung tu cung: Oxytocin co td co tu cung manh khi dang mang thai db cang gan cuoi thoi ky co thai, td co tu cung cua Oxytocin cang manh. Vi tac dung nay ma nhieu ng cho rang Oxytocin co lquan toi co che de. Tren 1 so loai dvat neu ko co Oxytocin dv nay ko de dc. o nguoi nong do Oxytocin tang trong khi de db tang trong gd cuoi. o nhung ng de kho con co tu cung yeu ta thg tiem truyen Oxytocin de lam tang con co tu cung
+ tac dung bai xuat sua: Oxytocin co td co cac TB bieu mo co la nhung TB nam thanh hang rao bao quanh nang tuyen sua. nhung TB nay co lai se ep vao nang tuyen voi ap luc 10 - 20 mmHg va day sua ra ong tuyen, khi dua tre bu thi nhan dc sua. tac dung nay cua Oxytocin dgl bai xuat sua, khac voi td gay bai xuat sua cua PRL
- dieu hoa bai tiet:
Binh thuong Cm Oxytocin huyet tg la 1 - 4 pmol/l. Oxytocin dc bai xuat do kick thick sinh hoc va tam ly.
+ kick thick truc tiep vao num vu: chinh dtac mut vu cua dua tre la nhung tin hieu kick thick dc truyen ve tuy song roi vung duoi doi lam kick thick cac noron o nhan canh n•o that va nhan tren thi. Nhung tin hieu nay dc truyen xuong thuy sau tuyen yen de gay bai tiet Oxytocin.
+ kick thick tam ly or kick thik he giao cam: vung duoi doi luon nhan dc cac tin hieu tu he limbic do vay tat ca nhung kick thick tam ly or he giao cam co lien quan den cam xuc deu co anh huong den vung duoi doi lam tang bai tiet Oxytocin va do vay tang bai xuat sua. tuy nhien neu nhung kick thick nay qua manh or keo dai thi co the uc che bai tiet Oxytocin va lam mat sua o cac ba me dang nuoI con.
