Hormones and liver mitochondria: Influence of growth hormone,thyroxine, testosterone,and insulin on thermotropic effects of respiration and fatty acid composition of membranes

The effects of hypophysectomy and subsequent administration of growth hormone, thyroxine, insulin, and testosterone were examined in rat liver for the relationship between the thermotropic effects on State 3 respiration (ADP induced) and fatty acid composition of the phospholipid fraction of intact mitochondria as well as of inner membrane vesicles. The Arrhenius profile for energy-linked (succinate) State 3 respiration of mitochondria from hypophysectomized rats lacked the discontinuity at 23.5 °C seen with mitochondria from normal rats. After injections of the hormones the discontinuity representing the transition temperature from gel to liquid crystalline state of lipids occurred at different temperatures: 18.5 °C for growth hormone, 26.0 °C for thyroxine, 19.5 °C for growth hormone + thyroxine, 27.6 °C for insulin, and 25.3 °C for testosterone. The energy of activation between 37.5 and 23.5 °C was 1.9 times greater for hypophysectomy than for controls. Growth hormone was the most effective in restoring the energy of activation to normal, above as well as below transition temperature. The effect of thyroxine appears to be due to a larger stimulation of the State 4 respiration than that of growth hormone, insulin, or testosterone, especially at higher temperatures. Phospholipids extracted from intact mitochondria or inner membrane vesicles of hypophysectomized rats contained less arachidonic acid (20:4) and more linoleic acid (18:2) than those of normal rats. In addition, the contents of some of the minor fatty acids were also changed. Calculated unsaturation index showed an 18.8 and 14.9% depletion in unsaturation in whole mitochondria and inner membranes, respectively. Among the different hormones used to treat the hypophysectomized rats, growth hormone was the most effective in restoring the transition temperature and fatty acid composition to normal levels and increasing the gain in body weight. Although the other hormones increased total unsaturation index to some extent, some of the individual fatty acids were affected differently. Good correlation exists between the unsaturation index of mitochondrial fatty acids and transition temperature of State 3 respiration. These results strongly suggest a role for the hormones, particularly growth hormone, in the control of mitochondrial membrane fluidity of hypophysectomized rat liver, through fatty acid composition of phospholipids.     

阿坝藏族自治州若尔盖晚更新世地层及哺乳类化石

文中记述阿坝藏族自治州若尔盖县境内黄河阶地堆积及其所产哺乳动物化石,并经 C~(14) 测定,化石距今约22650±300年,地质时代为晚更新世晚期.     

湖北竹溪植被的基本特征

竹溪县现有种子植物１２７科４８３属８６３种。地理成分复杂,联系广泛,以温带成分占主导地位,占非世界分布属的６４．８３％,热带分布属则占２９．３９％,木本植物占种子植物总数的４２．５９％,主要植补类型计７个植补型组,１０个植被型,４９个联系。地处竹溪中南部的云雾溪是目前亚热带区域保存较为完整,具有多方面保护价值的综合区,建议辟为自然保护区。     

云南元谋小河地区古猿地点的小型猿类化石

本文记述的云南元谋小河地区古猿地点发现的一种小型猿类。它的牙齿形态比晚中新世的禄丰粗壮池猿进步。而牙齿的某些形态介于粗壮池猿和现生长臂猿之间,它的发现为探讨现生长臂猿的起源与进货提供了新的化石依据。依哺乳动物群的初步研究,其时代稍晚于禄丰古猿地点的时代。鉴于它的形态特征和地史分布,作者将它订为一新属新种：进步滇猿Ｄｉａｎｏ ｐｉｔｈｅｃｕｓ ｐｒｏｇｒｅｓｓｕｓ ｇｅｎ．ｅｔ ｓｐ．ｎｏｖ。     

贵州沿河土地坳下奥陶统牙形石

本文报道了采自贵州沿河土地坳下奥陶统的牙形石,计有２５属３９种,根据牙形石组合特片分析,认为其与黔北其它地区下奥陶统牙形石组合面貌基本一致,属北大西洋牙形石动物地理区。     

晋西北黄河岸边新发现的旧石器地点

在山西省河曲县河会村附近发现一个旧石器地点,从中发现石制品十多件,其地质时代为中更新世晚期。     

元谋新第三纪食肉动物化石的初步观察

本文对云南元谋盆地产古猿化石地点的部分食肉类化石进行了初步观察分类,认为它们的时代似应稍晚于禄丰,相当上新世早期,估计距今5-6百万年.     

山西朔县种子植物区系及其生态经济意义

朔县(现朔州市朔城区)植物种属相对丰富,具有维管束植物938种,隶属于420属,105科。其植物区系主要起源于古北大陆;种子植物属的地理成分复杂多样,以温带成分占绝对优势,具有典型的温带草原性质;与相邻地区植物区系的比较分析表明,联系最为密切的是蒙古草原植物区系,其次是黄土高原植物区系。该县植物资源利用应采取的对策是:既要合理开发利用,又要加强物种的保护。     

湖南蓝山县端午药市的瑶药调查

中国南方一些少数民族地区民间“端午药市”流传至今,体现了民族医药的独具特色及其深远影响。为了解瑶族端午药市交易现状和发掘民族医药传统知识,采用民族植物学等方法对湖南省蓝山县端午药市进行调查,完成包括基原、地方名、药用部位、用途和用法、出现频度等内容的药用植物编目。结果表明:蓝山县端午药市药用植物种类丰富,共收集鉴定103科 222属262种,药用植物种类广泛分布于各科和各属中,其中种类较多的科有五加科(11种)、茜草科(11种)、菊科(11种)、百合科(10种)、唇形科(9种)、蝶形花科(8种)、芸香科(7种)。药市药浴植物畅销且种类多样,达94种,占总数的35.9%,体现瑶族在治疗疾病上以预防保健为主的理念。经统计药市上均未被国家药典和地方标准收录的药用植物有131种,占总数的50.2%,成为发掘新药源、新用途的潜在资源。对端午药市售药者年龄的调查发现,售药者的年龄主要集中在50～59岁间,占总人数的67%,40岁以下的仅占总人数的3%,可见民族药用传统知识的传承存在传承人老龄化、潜在传承人数量锐减的现象。此外,还对药市交易药用植物的种类组成和民族药用特色进行分析,探讨了端午药市对药用传统知识保护与传承的影响,并对蓝山端午药市的可持续发展提出了建议。