Influence of rearing water temperature on induced gonadal development and spawning behaviour of tropical green mussel,Perna viridis

ObjectiveTo standardize the technique of induced breeding and spawning of green mussel Perna viridis (P. viridis), in captivity.MethodsIn Experiment-A, the temperature was increased at a rate of 2 °C/5 days interval. In Experiment-B, a rise of 3 °C/5 days was practiced, whereas in Experiment C and D, respectively 4 and 5 °C was increased in 5 days interval. The temperature was maintained constant at 20 °C in the Control.ResultsThe increase in temperature showed a progressive effect on the gonadal development of mussels. The gonads ripped at 30 to 32 °C in all the experimental tanks, irrespective of the difference in temperature hike. Complete spawning in P. viridis was achieved by gradually raising the temperature from 20 to 35 °C at a rate of 3 or 4 °C/5 days.ConclusionAccording to the present study temperature induced spawning method is very simple and cost effective and can accelerate the production of mussel seeds in hatchery units and further stock improvement through genetic manipulation.     

Plastic effect of soiled bedding on the structure of synapses in rat accessory olfactory bulb

The effects of exposure to soiled bedding on synaptic morphology in the accessory olfactory bulb (AOB) were examined in adult male rats. Forty-day-old male rats were isolated. One group was exposed to bedding soiled by male and female rats (EC). Another group was exposed only to male-soiled bedding (SC). A third group was exposed to clean bedding (IC). After 2 months, the animals were sacrificed for electron microscopy. The size and the numerical density of synapses were measured in the glomerulus and the granule cell layer. In the glomerulus, the mean size of the synapses was significantly greater in the EC than in the IC group, whereas that in the SC group appeared to be intermediate between those in the EC and the IC groups but was not significantly different from those in the EC and the IC groups. There was no statistically significant difference in the density of synapses among the three groups. Synapses in the granule cell layer are classified into two types: (1) perforated synapses, which are characterized by discontinuities in their postsynaptic thickenings, and (2) nonperforated synapses. The mean size of perforated synapses was significantly greater in the EC than in the IC and SC groups; however, no statistically significant difference was observed in the size of nonperforated synapses among the three groups. Moreover, no statistically significant difference was observed in the numerical densities of either perforated or nonperforated synapses among the three groups. These results suggested that exposure to a more complex soiled bedding environment (i.e., to bedding soiled by both male and female rats) can induce greater structural changes of the synapses in the AoB of male adult rats. © 1995 Wiley-Liss, Inc.     

Effects of intracerebroventricular administration of pituitary adenylate cyclase-activating polypeptide (PACAP) on the motor activity and reserpine-induced hypothermia in murines

We investigated the effects of i.c.v. administration of pituitary adenylate cyclase-activating polypeptide (PACAP) on the spontaneous motor activity and reserpine-induced hypothermia in murines. The administration of PACAP (1 or 2 nmol) caused a dose-dependent increase in both spontaneous motor activity and rearing behavior in the rat. The peptide (0.1 or 0.2 nmol) counteracted reserpine-induced hypothermia in a dose-dependent manner in mice. On the other hand, i.c.v. injection of vasoactive intestinal polypeptide, which is structurally similar to PACAP, at a dose similar to that of PACAP (2 nmol in rats, 0.2 nmol in mice) did not show a significant effect on either behavior or body temperature. Therefore, the stimulating effect of PACAP observed here may be mediated by PACAP-specific (type I) receptors. PACAP was more potent and longer-lasting than a known potent stimulating peptide, thyrotropin-releasing hormone, in both stimulating motor activity and counteracting reserpine-induced hypothermia. Results of the present study, in combination with those of previous studies identifying endogenous PACAP in the brain, suggest that PACAP may play an important role in the CNS as a stimulant in regulating motor activity and body temperature.     

Effect of differential rearing on synapses and soma size in rat medial amygdaloid nucleus

The effects of differential rearing on synaptic morphology and neuronal size were examined in the medial amygdaloid nucleus (MAN) of adult rats. Forty-day-old male rats were housed in one of three ways: individually (isolated condition, IC); with four males per cage (unisexual condition, UC); or with two males and two females per cage (social condition, SC). After 2 months, the animals were prepared for electron and light microscopy Although there was no statistically significant difference in number of synapses per unit volume in MAN, the number of perforated (P) synapses, which are characterized by discontinuities in the postsynaptic density, were significantly greater in the UC and the SC than in the IC. The length of synaptic contact zone of P synapses was also longer in both the UC and the SC compared with the IC, whereas the length of nonperforated synapses was longer only in the SC. Some area was also larger in the SC compared with the IC. These results demonstrate that exposure to different rearing conditions, in which the pheromonal environment can be substantially different, can induce striking morphological changes in both synapses and neurons in the MAN of adult rats. © 1993 Wiley-Liss, Inc.     

Effects of intrastriatal and intracortical scopolamine on behavior in rats

The anticholinergic drug scopolamine (20 micrograms, 30 micrograms, 40 micrograms) or its vehicle was injected unilaterally into the dorsal anterior striatum or overlying rostral neocortex in rats in order to examine the role of each region in contralateral postural deviation and stereotyped rearing. Scopolamine-induced contralateral deviation was observed in all subjects with striatal injections (p less than 0.01), and was of the same magnitude at all dose levels. Intracortical scopolamine did not induce contralateral deviation. However, stereotyped rearing was elicited from both the striatum and neocortex (p less than 0.01) at the two highest dose levels of scopolamine. Thus the mechanisms for contralateral deviation and stereotyped rearing differ both with respect to brain region and drug sensitivity.     

无菌猪的制备与微生物质量控制

菌群与宿主相互关系等热点研究促进了对无菌动物需求的迅猛发展。无菌猪作为一种特殊的模式动物,其在科学研究中不仅排除了背景微生物因素的影响,而且与常用的无菌小鼠相比,其在解剖、生理、代谢等方面与人更为相似,因此在生命科学研究领域具有重要的应用价值。本文结合现有国外无菌猪研究进展和本实验室在无菌猪研究积累,就无菌猪的制备与微生物质量控制进行简要探讨。     

Dopamine-sensitive alternation and collateral behaviour in a Y-maze: Effects of d-amphetamine and haloperidol

The degree of alternation of arm choice in a Y-maze was examined on 15-min tests over 4 days in rats treated (IP) with saline, amphetamine (0.5 or 2.0 mg/kg) or pretreated with haloperidol (0.08 mg/kg) in each condition prior to test. On day 1 amphetamine-treated animals chose arms at random, but from day 2–4 those receiving the higher dose perseverated their choice. Controls maintained alternation. These effects could be prevented by haloperidol pretreatment. Amphetamine treatment increased the frequency of rearing at the middle, choice-point of the maze more than at the end of an arm. The increase at the mid-point was suppressed by haloperidol pretreatment from day 1 and at the end of an arm from day 2. Amphetamine induced an increase in head-turning/looking that was suppressed by haloperidol from day 2. The effect of haloperidol in increasing the duration of an item of looking or rearing at the end of an arm also started later in testing. Two effects are postulated to have occurred: (i) a conflict on day 1 between novelty-controlled sensory or attentional effects that leads to an alternation of arm choice and amphetamine-induced dopaminergic activity that facilitates an alternation of behavioural responses. The result was random choice and increased rearing at the choice point. (ii) On days 2–4 the drug-induced effects on switching motor responses came to control behaviour.     

精神分裂症患者家庭环境、父母教养方式以及亲密度和适应性的调查分析

目的　探索精神分裂症患者的家庭环境、父母教养方式以及亲密度和适应性的特点。方法　采用家庭环境量表 (中文版 ) ) (FES -CV)、父母教养方式评价量表 (EMBU)及家庭亲密度和适应性量表 (中文版 ) (FACESII-CV)对 110例精神分裂症患者 (研究组 )进行评定 ,并与 110例正常受试者 (对照组 )加以比较。结果　①同正常对照组相比 ,患者家庭表现为低亲密度、低情感表达、低成功性、低组织性以及高矛盾性和控制性差 (P <0 0 5或P<0 0 1)。②在教养方式上 ,患者父亲表现为低情感温暖、高惩罚严厉、过分干涉和拒绝否认 (P <0 0 1) ;而母亲表现为低情感温暖、高拒绝否认、惩罚严厉和偏爱被试 (P <0 0 5和P <0 0 1)。③在亲密度和适应性方面 ,患者家庭的实际亲密度、实际适应性、理想亲密度和理想适应性均较对照组为差 (P <0 0 1)。结论　患者的家庭环境、父母教养方式以及亲密度和适应性方面均存在着诸多方面的问题 ,可能对精神分裂症的发病起重要作用。     

父母教养方式对子女焦虑的影响研究

目的探讨父母教养方式对子女特质焦虑的影响。方法采用"家庭教养方式问卷"(EMBU)和"特质焦虑问卷"(TAI),对306名被试进行调查,采用典型相关分析和层次回归分析。结果EMBU和TAI典型相关系数显著,层次回归结果表明,父母教养方式对特质焦虑有显著影响。结论父母教养方式对子女特质焦虑程度有显著影响。     

The 5-HT1A receptor and behavioral stimulation in the rat: effects of 8-OHDPAT on spontaneous and cocaine-induced behavior

Rationale The contribution of the 5-HT_1A somato-dendritic autoreceptor populations to spontaneous and cocaine-induced locomotion is unclear.Objectives To use a low dose range of ±8-hydroxy-2-(di-n-propylamino)tetralin (8-OHDPAT) to preferentially stimulate 5-HT_1A autoreceptors and a medium 8-OHDPAT dose range to stimulate both 5-HT_1A autoreceptors and postsynaptic receptors as pretreatments prior to either saline or cocaine.Methods In experiment 1, either a medium dose of 8-OHDPAT (0.4 mg/kg) or a low dose (0.05 mg/kg) was given as pretreatments 20 min before five separate 20-min open-field tests. In experiment 2, the pretreatments were changed to a low dose range of 8-OHDPAT (0.01–0.05 mg/kg), with or without WAY 100635 (0.01–0.05 mg/kg). In experiment 3, the 8-OHDPAT pretreatments (0.01, 0.025 or 0.05 mg/kg) were administered 20 min prior to saline or cocaine (10 mg/kg) tests. In experiment 4, a medium dose range (0.2–0.3 mg/kg) was given 20 min prior to saline or cocaine (10 mg/kg) tests.Results Experiment 1 showed that 8-OHDPAT (0.4 mg/kg) tended to increase locomotor activity but that pretreatment with 0.05 mg/kg severely suppressed locomotor activity. In experiment 2, 8-OHDPAT in the low dose range inhibited locomotor activity and this effect was reversed by co-administration of WAY 100635. Experiment 3 showed that the low-dose 8-OHDPAT pretreatment reduced locomotor activity in saline but not cocaine tests. In experiment 4, 8-OHDPAT in the medium dose range enhanced locomotor activity in cocaine tests.Conclusions It is suggested that the facilitatory effect of 8-OHDPAT on cocaine-induced locomotor stimulation is mediated by inhibition of 5-HT_1A somato-dendritic autoreceptors.