小蘖碱、巴马亭及四氢巴马亭(延胡索乙素)对大鼠促皮质素释放的影响

我们曾报告延胡索乙素有刺激大鼠促皮质素(ACTH)释放的作用,本文报告在化学结构上与延胡索乙素相似的两种药物——小蘗碱及巴马亭(Palmatine)对大鼠垂体——肾上腺皮质功能的影响,以及延胡索乙素对ACTH释放的抑制作用。小蘗碱5或10毫克/公斤,巴马亭25或50毫克/公斤皮下注射一次,都能引起大鼠肾上腺内维生素C含量明显降低,对去垂体大鼠肾上腺的维生素C则无影响,戊巴比妥钠麻醉可明显抑制小蘗碱的降低肾上腺维生素C作用,唯对巴马亭的这种作用却无影响,在戊巴比妥钠麻醉的基础上,吗啡能完全抑制巴马亭的降低肾上腺维生素C作用。每日给大鼠注射延胡索乙素1次(70毫克/公斤),连续6次后,对低温(8℃或4℃1小时)刺激引起的ACTH释放有明显抑制作用。总括我们的结果,延胡索乙素、小蘗碱及巴马亭这三种化学结构相似的药物,都能刺激大鼠ACTH的释放,但其作用机制或部位可能彼此不同,此外,延胡索乙素的多次注射还可抑制ACTH的释放,这些作用的不同可能与上述三药的化学结构特别是第3环的饱和与否有关系。

Comparative Study on the ACTH-Releasing Activities of Berberine,Palmatine and Tetrahydropalmatine (Corydalis B) in the Rat

Corydalis B has been reported to have a stimulatory action on the release of ACTH in rats. Since the structural formulae of berberine and palmatine closely resemble that of corydalis B, an attempt was made to compare the effect of these three compounds on the secretion of ACTH by the pituitary. The depletion of adrenal ascorbic acid of rats was used as the criterion for the secretion of ACTH. For comparison, some of the results described in the previous paper are also included here. Subcutaneous injection of corydalis B (25,50mg kg), berberine (5,10mg/kg)or palmatine (25, 50 mg/kg) depleted significantly the adrenal ascorbic acid content of the rat. The action of these three compounds was abolished by hypophysectomy. Pretreatment of rats with pentobarbital (40 mg/kg) almost completely inhibited the adrenal ascorbic acid depleting action of corydalis B and of berberine, but not that of palmatine. However, the depletion of adrenal ascorbic acid by palmatine was inhibited completely by prior injection of morphine (20mg/kg) in rats under pentobarbital anesthesia. After six consecutive daily injections of corydalis B (70 mg/kg/daily) the rats developed tolerance (or adaptation) to the stimulatory action of the compound on the pituitary gland, while berberine and palmatine lacked this property. In addition, corydalis B, injected repeatedly at the daily dosage of 70 mg/kg for 6 consecutive days, could inhibit the release of ACTH activated by cold stress (8℃ or 4℃ for 1 hour) in rats. The above results indicate that the effects of corydalis B, berberine and palmatine on the pituitary-adrenal system are similar in certain aspects, but different in each others. This is presumably due to the differences in the molecular structure paticularly the third ring of the compounds.