Vasoconstriction ndi mawonekedwe a thupi omwe amachititsa kuti mitsempha ya mitsempha ya thupi ichepetse ndikuchepetsa kwa minofu yomwe imapanga zotengera za mitsempha (mitsempha, mitsempha). Itha kuyambitsidwa pazifukwa zingapo, koma mulimonse momwe zingayendere mwachangu pakusintha kofunikira, makamaka kuyimitsa magazi.

Vasoconstriction ndimachitidwe achilengedwe omwe amakhala ndi kuchepa kwa mitsempha yamagazi, ndikuchepetsa kwa ulusi wa minofu yake. Zochita zake zotsutsana ndizofanana ndi vasodilation; mayendedwe onsewa akuphatikiza zomwe zimatchedwa vasomotricity.

Vasoconstriction ili ndi vuto lochepetsa, mwachitsanzo, kutuluka magazi pakakhala chotupa chamagazi. Ili ndiye gawo loyamba la hemostasis. Malo opangira mitsempha ya vasoconstrictor ndi omwe amayambitsa izi, komanso mahomoni angiotensin, adrenaline ndi noradrenaline. Chifukwa chake Vasoconstriction imapangitsa kuchepa kwa magazi m'thupi lomwe likufunsidwa. Pamwamba pa chotengera chake pamamatira, zimamatira.

Pali zinthu zingapo zomwe zimayambitsa vasoconstriction mthupi. Chofala kwambiri ndi kuwonongeka kwa maselo am'minyewa, omwe mitsempha yake yamagazi, mwakuletsa, imaletsa magazi.

Zinthu zina zimayambitsanso izi:

• Serotonin, yotulutsidwa ndi ma platelet;
• Kukhazikitsa kwa zolandila zopweteka zomwe zimadutsa mumanjenje (catecholamines, adrenaline, noradrenaline);
• Poizoni kapena zinthu zina zomwe zimapezeka m'zakudya (mwachitsanzo, caffeine).

Kupitilira pazifukwa zoyambazi, makina a vasoconstriction amatha kukhazikitsidwa pakukhazikitsa kusinthana kwa kutentha m'thupi, komwe kumakhudza mitsempha, endocrine, mtima ndi kupuma.

Kutentha kwa thupi kukatsika, nthawi yozizira kwambiri mwachitsanzo, munthu amatha kuwona mawonekedwe a vasoconstriction odulira: chodabwitsachi chimapangitsa kupatula zotumphukira zapakati pa thupi. Kuchepetsa m'mimba mwake pamitsempha yamagazi pathupi pathu kumakhala ndi zotsatira zakubwezeretsanso "gradient" (kusiyana) kutentha pakati pa khungu ndi ziwalo za mtima, mapapo, ubongo, impso. Kuphatikizidwa ndi kuthamanga kwa magazi ndi kuwonjezeka kwa kamvekedwe ka dongosolo lamanjenje, vasoconstriction imeneyi imakulitsa kugunda kwa mtima. Izi zimabweretsa kuwonjezeka kwa 10% m'magazi ofiira ndi oyera, ma platelets, komanso cholesterol ndi fibrinogen. Zotsatira: kuwonjezeka kwa mamasukidwe akayendedwe wamagazi mozungulira 20%.

Pomaliza, thupi lanu likakhala kuzizira, chipinda chamkati chimazungulira zokha ndikuwotcha mphamvu zambiri. Zofunikira pamtima komanso zofunika pa oxygen zimakulanso.

Kupsinjika, udindo? 

Komanso, kupanikizika kumathanso kuchititsa kuti vasoconstriction. Pogwiritsira ntchito adrenaline, kutumiza uthenga wopanikizika wofika nthawi, zombozi zidzagwira ntchito yolimbitsa kukula kwake, kwakanthawi.

Chizindikiro

Nicotine imayambitsa vasoconstriction m'mitsempha, imachepetsa kutuluka kwa magazi, chifukwa chake kuchuluka kwa mpweya woperekedwa kumatumba ndi poizoni zomwe zimachotsedwa m'matumba omwewo.

Vasoconstriction iyi imasinthidwa ndipo imasowa patatha maola ochepa mutasuta. Vasoconstriction imakhala yokhazikika masana, chifukwa cha omwe amasuta kwambiri.

Matenda omwe angakhalepo

Pomaliza, vasoconstriction imatha kukhala chizindikiro cha matenda omwe angakhalepo, kuledzera kapena envenomation. Mwachitsanzo, matenda a Raynaud amawonetsedwa ndi mitsempha yaying'ono kumapeto kwa thupi (manja, mapazi), makamaka nthawi yozizira kapena kupsinjika. Matendawa amachititsa kuti magazi asatayike m'deralo komanso kupweteka magazi akamabwerera kumadera omwewo.

Vasoconstriction imatha chifukwa cha mankhwala osokoneza bongo, kuti achepetse magazi ena munthawi zina.

Kusunthika kwamtunduwu ndikotsutsana ndi vasoconstriction motero kumafanana ndi kuwonjezeka kwa kukula kwa ziwiyazo mwakuchepetsa.

Kuchulukaku kumatheka chifukwa cha kupumula kwa minofu yozungulira mitsempha.

Zomwe zimayambitsa kusungunuka ndi:

• Kutentha;
• Matenda, poyizoni, envenomation;
• Thupi lawo siligwirizana, yotupa (edema);
• Mowa umakhala ndi mphamvu ya vasodilator ndipo umachepetsa mitsempha yamagazi muubongo;
• Amayambitsa mankhwala, monga mankhwala oopsa.

Pachifukwa chotsatirachi, munthu yemwe ali ndi matenda oopsa kwambiri amakhala ndi zotengera zomwe "ndizocheperako" kuti magazi azithamanga pamitsempha yawo, kuwawononga. Chifukwa chake tigwiritsa ntchito mankhwala ochepetsa ziwiya zake kuti tichepetse kuthamanga kwa magazi.