Department of Health Sciences, University of Jaén, 23071 Jaén, Spain.
Department of Physiology, Faculty of Health Sciences, Ceuta, University of Granada, 18071 Granada, Spain.
Int J Mol Sci. 2021 Jul 22;22(15):7823. doi: 10.3390/ijms22157823.
In the present study, we analyzed the activity of several aminopeptidases (angiotensinases) involved in the metabolism of various angiotensin peptides, in pituitary and adrenal glands of untreated Wistar-Kyoto (WKY) and spontaneously hypertensive rats (SHR) or treated with the antihypertensive drugs captopril and propranolol or with the L-Arginine hypertensive analogue L-NG-Nitroarginine Methyl Ester (L-NAME). Intra- and inter-gland correlations between angiotensinase activities were also calculated. Membrane-bound alanyl-, cystinyl-, and glutamyl-aminopeptidase activities were determined fluorometrically using aminoacyl-β-naphthylamide as substrates. Depending on the type of angiotensinase analyzed, the results reflect a complex picture showing substantial differences between glands, strains, and treatments. Alanyl-aminopeptidase responsible for the metabolism of Ang III to Ang IV appears to be the most active angiotensinase in both pituitary and adrenals of WKY and particularly in SHR. Independently of treatment, most positive correlations are observed in the pituitary gland of WKY whereas such positive correlations are predominant in adrenals of SHR. Negative inter-gland correlations were observed in control SHR and L-NAME treated WKY. Positive inter-gland correlations were observed in captopril-treated SHR and propranolol-treated WKY. These results may reflect additional mechanisms for increasing or decreasing systolic blood pressure in WKY or SHR.
在本研究中，我们分析了几种参与各种血管紧张肽代谢的氨肽酶（血管紧张素酶）的活性，这些酶存在于未治疗的 Wistar-Kyoto（WKY）和自发性高血压大鼠（SHR）的垂体和肾上腺中，或用抗高血压药物卡托普利和普萘洛尔或 L-精氨酸高血压类似物 L-NG-硝基精氨酸甲酯（L-NAME）治疗。还计算了血管紧张素酶活性的腺体间和腺体内相关性。使用氨酰-β-萘基酰胺作为底物，通过荧光法测定膜结合的丙氨酰、半胱氨酰和谷氨酰氨肽酶活性。根据分析的血管紧张素酶类型，结果反映了一个复杂的情况，表明腺体、品系和治疗之间存在很大差异。负责将血管紧张素 III 代谢为血管紧张素 IV 的丙氨酰氨肽酶似乎是 WKY 垂体和肾上腺中最活跃的血管紧张素酶，尤其是在 SHR 中。无论是否治疗，WKY 垂体中观察到的大多数正相关，而 SHR 肾上腺中观察到的正相关则占主导地位。在对照 SHR 和 L-NAME 治疗的 WKY 中观察到负的腺体间相关性。在卡托普利治疗的 SHR 和普萘洛尔治疗的 WKY 中观察到正的腺体间相关性。这些结果可能反映了 WKY 或 SHR 中增加或降低收缩压的额外机制。
