Corazza J P, Vega G W, Roson M I, de la Riva I J, Pellegrino de Iraldi A
Departamento de Biología Celular e Histologia, Facultad de Medicina, Universidad de Buenos Aires.
Medicina (B Aires). 1993;53(6):497-502.
The heart has an endocrine activity which depends on the secretion of a natriuretic, diuretic and hypotensive factor contained in osmophilic, secretory granules localized in the myocardiocytes and called "atrial specific granules" (the atrial natriuretic factor, ANF). In this paper, the relationship between these specific granules and renovascular hypertension elicited by the constriction of both renal arteries was investigated at the electron microscope level during the acute, subacute and chronic phases of hypertension. Male Wistar CHbb THOM rats were divided in three groups: 1) clipped rats; 2) sham operated rats; 3) ether anesthesia as unique manoeuver 48 h before decapitation. Blood pressure increased progressively after the constriction of both renal arteries. The atrial specific granules were not affected by ether anesthesia alone; 48-72 h after clipping the granules almost disappeared and this situation persisted up to the 6th week. In sham operated rats the picture was very similar to the clip rats 48 and 72 h after surgery (severe granule disappearance); in contrast, at one, two and six weeks after surgery, the granularity of cardiomyocytes in sham rats was absolutely restored. It is concluded that: 1) similarities in morphology of atrial specific granules in sham and clip rats 48 and 72 h after surgery would suggest that stress plays a primary role in determining the observed images; 2) thereafter, the contrast between sham and clip rats 1, 2 and 6 weeks after surgery would indicate that the ANF is linked to the subacute and chronic regulation of renovascular hypertension.
心脏具有内分泌活性，这依赖于心肌细胞中嗜锇性分泌颗粒所包含的一种利钠、利尿和降压因子的分泌，这种颗粒被称为“心房特异性颗粒”（心房利钠因子，ANF）。在本文中，利用电子显微镜技术，研究了在肾血管性高血压的急性、亚急性和慢性阶段，这些特异性颗粒与双侧肾动脉狭窄引发的肾血管性高血压之间的关系。雄性Wistar CHbb THOM大鼠被分为三组：1）夹闭组大鼠；2）假手术组大鼠；3）在断头前48小时仅用乙醚麻醉的大鼠。双侧肾动脉狭窄后血压逐渐升高。单独的乙醚麻醉不会影响心房特异性颗粒；夹闭后48 - 72小时颗粒几乎消失，这种情况一直持续到第6周。在假手术组大鼠中，术后48小时和72小时的情况与夹闭组大鼠非常相似（颗粒严重消失）；相反，在术后1周、2周和6周时，假手术组大鼠心肌细胞的颗粒度完全恢复。得出以下结论：1）术后48小时和72小时假手术组和夹闭组大鼠心房特异性颗粒形态的相似性表明，应激在决定观察到的图像中起主要作用；2）此后，术后1周、2周和6周假手术组和夹闭组大鼠之间的差异表明，ANF与肾血管性高血压的亚急性和慢性调节有关。
