Hypothalamic-pituitary-adrenal axis
 Hypothalamic-pituitary-adrenal axis | |
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biological system (en)  |
Axis na hypothalamic-pituitary-adrenal (HPA axis ko HTPA axis) wani tsari ne mai rikitarwa na tasiri kai tsaye da kuma ma'amala tsakanin abubuwa uku: thalamus" id="mwEw" rel="mw:WikiLink" title="Hypothalamus">hypothalamus (wani ɓangare na kwakwalwa da ke ƙasa da thalamus), glandun na pituitary (tsarin siffar wake da ke ƙasa na hypothalamus), da adrenal (wanda ake kira "suprarenal") gland (ƙananan, conical gabobin a saman koda). Wadannan tsarin da hulɗarsu sun zama HPA axis.
Tsarin HPA babban tsarin neuroendocrine ne wanda ke sarrafa martani ga damuwa kuma yana daidaita hanyoyin jiki da yawa, gami da narkewar abinci, martanin garkuwar jiki, yanayi da motsin rai, ayyukan jima'i, da adana makamashi da kashe kuɗi. Ita ce hanyar da aka saba amfani da ita don hulɗa tsakanin gland, hormones, da sassan tsakiyar kwakwalwa waɗanda ke shiga tsakani na ciwon daidaitawa na gabaɗaya (GAS).
Duk da cewa ana samar da hormones na steroid galibi a cikin ƙwayoyin halitta masu ƙashi, rawar da HPA da corticosteroids ke takawa a cikin amsawar damuwa abu ne mai matuƙar muhimmanci wanda hakan ke sa a iya samun tsarin kama da juna a cikin ƙwayoyin halitta marasa ƙashi da kuma ƙwayoyin halitta masu kama da juna .
Tsarin HPA, tsarin hypothalamic-pituitary-gonadal (HPG), tsarin hypothalamic-pituitary-thyroid (HPT), da kuma tsarin hypothalamic-neurohypophyseal su ne manyan tsarin neuroendocrine guda huɗu waɗanda hypothalamus da pituitary ke aiki kai tsaye a kansu.
Ilimin Halittar Jiki
[gyara sashe | gyara masomin]Muhimman abubuwan da ke cikin axis na HPA sune: [1]
- Tsarin tsakiya na hypothalamus : Yana ɗauke da ƙwayoyin neuroendocrine waɗanda ke haɗa kuma suna fitar da vasopressin da corticotropin-releasing hormone (CRH).
- Lobe na gaba na glandar pituitary : CRH da vasopressin suna motsa lobe na gaba na glandar pituitary don samar da hormone adrenocorticotropic (ACTH), wanda aka sani da corticotropin .
- Kwayar halittar adrenal : Tana samar da hormones na glucocorticoid (galibi cortisol a cikin mutane) a matsayin martani ga ƙarfafawa daga ACTH. Glucocorticoids, bi da bi, suna mayar da martani ga hypothalamus da pituitary (don danne samar da CRH da ACTH) a cikin zagayowar amsawa mara kyau .
Ana fitar da CRH da vasopressin daga tashoshin jijiyoyin neurosecretory a tsakiyar matsayi . Ana jigilar CRH zuwa ga pituitary na gaba ta hanyar tsarin jijiyoyin jini na ƙwayar hypophyseal kuma ana jigilar vasopressin ta hanyar jigilar axonal zuwa glandar pituitary ta baya . A can, CRH da vasopressin suna aiki tare don ƙarfafa fitar da ACTH da aka adana daga ƙwayoyin corticotrope. Ana jigilar ACTH ta jini zuwa ga adrenal cortex na glandar adrenal, inda yake hanzarta haɓaka biosynthesis na corticosteroids kamar cortisol daga cholesterol . Cortisol babban hormone ne na damuwa kuma yana da tasiri akan kyallen jiki da yawa, gami da kwakwalwa. A cikin kwakwalwa, cortisol yana aiki akan nau'ikan masu karɓa guda biyu: masu karɓar mineralocorticoid da masu karɓar glucocorticoid, kuma waɗannan suna bayyana ta nau'ikan neurons daban-daban. Ɗaya daga cikin mahimman abubuwan da glucocorticoids ke nufi shine hypothalamus, wanda shine babban cibiyar sarrafawa na axis na HPA. [2]
Ana iya ɗaukar Vasopressin a matsayin "hormone na kiyaye ruwa" kuma ana kiransa da "hormone na antidiuretic (ADH)". Ana fitar da shi lokacin da jiki ya bushe kuma yana da tasirin kiyaye ruwa mai ƙarfi akan koda. Hakanan yana da ƙarfin vasoconstrictor .
Muhimmanci ga aikin HPA axis sune wasu daga cikin madaukai masu zuwa na amsawa:
aiki
[gyara sashe | gyara masomin]Sakin hormone mai sakin corticotropin (CRH) daga hypothalamus yana shafar damuwa, motsa jiki, rashin lafiya, matakan cortisol a cikin jini da kuma zagayowar barci/farkawa ( circadian rhythm ). A cikin mutane masu lafiya, cortisol yana tashi da sauri bayan farkawa, yana kaiwa kololuwa cikin mintuna 30-45. Sannan a hankali yana faɗuwa a kan yini, yana kaiwa ga wani wuri a tsakiyar dare. Wannan ya yi daidai da zagayowar ayyukan hutawa na kwayoyin halitta. An danganta zagayowar circadian cortisol mai laushi da rashin daidaituwa da ciwon gajiya na yau da kullun, [3] rashin barci [4] da gajiya . [5]
Tsarin HPA yana da muhimmiyar rawa wajen daidaita tsarin homeostatic da yawa a cikin jiki, gami da tsarin metabolism, tsarin zuciya da jijiyoyin jini, tsarin garkuwar jiki, tsarin haihuwa da tsarin jijiyoyi na tsakiya . Tsarin HPA yana haɗa tasirin jiki da na psychosocial don ba da damar halitta ta daidaita yadda ya kamata da muhallinta, amfani da albarkatu, da kuma inganta rayuwa.
Haɗin jiki tsakanin sassan kwakwalwa kamar amygdala, hippocampus, prefrontal cortex da hypothalamus yana sauƙaƙa kunna axis na HPA. Ana sarrafa bayanan motsin rai da suka isa gefen amygdala kuma a isar da su zuwa tsakiya na amygdala, wanda daga nan ya bayyana zuwa sassa da yawa na kwakwalwa da ke da hannu a cikin martanin tsoro. A hypothalamus, motsin alamun tsoro yana kunna tsarin juyayi mai tausayi da tsarin daidaitawa na axis na HPA.
Ƙara yawan samar da cortisol a lokacin damuwa yana haifar da ƙaruwar samuwar glucose domin sauƙaƙe faɗa ko guduwa . Baya ga ƙaruwar samuwar glucose kai tsaye, cortisol kuma yana danne hanyoyin rayuwa masu matuƙar wahala na tsarin garkuwar jiki, wanda ke haifar da ƙarin samuwar glucose.
Glucocorticoids suna da ayyuka masu mahimmanci da yawa, gami da daidaita halayen damuwa, amma fiye da haka suna iya zama masu illa. Ana kyautata zaton cewa rugujewar hippocampus a cikin mutane da dabbobi da ke fuskantar matsananciyar damuwa yana faruwa ne sakamakon tsawaita amfani da glucocorticoids mai yawa. Rashin isasshen hippocampus na iya rage albarkatun ƙwaƙwalwa da ake da su don taimakawa jiki wajen tsara martanin da suka dace ga damuwa. [6]
Manazarta
[gyara sashe | gyara masomin]- ↑ "Getting to know the HPA axis". www.nrdc.org (in Turanci). 2015-05-18. Archived from the original on 2023-08-10. Retrieved 2023-08-08.
- ↑ Tasker, Jeffrey G.; Herman, James P. (14 July 2011). "Mechanisms of rapid glucocorticoid feedback inhibition of the hypothalamic–pituitary–adrenal axis". Stress. 14 (4): 398–406. doi:10.3109/10253890.2011.586446. PMC 4675656. PMID 21663538.
- ↑ MacHale SM, Cavanagh JT, Bennie J, Carroll S, Goodwin GM, Lawrie SM (November 1998). "Diurnal variation of adrenocortical activity in chronic fatigue syndrome". Neuropsychobiology. 38 (4): 213–7. doi:10.1159/000026543. PMID 9813459. S2CID 46856991.
- ↑ Backhaus J, Junghanns K, Hohagen F (October 2004). "Sleep disturbances are correlated with decreased morning awakening salivary cortisol". Psychoneuroendocrinology. 29 (9): 1184–91. doi:10.1016/j.psyneuen.2004.01.010. PMID 15219642. S2CID 14756991.
- ↑ Pruessner JC, Hellhammer DH, Kirschbaum C (1999). "Burnout, perceived stress, and cortisol responses to awakening". Psychosom Med. 61 (2): 197–204. doi:10.1097/00006842-199903000-00012. PMID 10204973.
- ↑ Frankiensztajn, Linoy Mia; Elliott, Evan; Koren, Omry (June 2020). "The microbiota and the hypothalamus-pituitary-adrenocortical (HPA) axis, implications for anxiety and stress disorders". Current Opinion in Neurobiology. 62: 76–82. doi:10.1016/j.conb.2019.12.003. PMID 31972462. S2CID 210836469.