Hippocampal 5-hydroxytryptamine synthesis is greater in female rats than in males and more decreased by the 5-HT1A agonist 8-OH-DPAT.
TL;DR: Brain regional 5-hydroxytryptamine (5-HT) and/or 5-HIAA concentrations tended to be slightly higher in female rats than in males but differences were substantial only in the hippocampus where female values were 34% and 36% higher respectively, consistent with the synthesis rates of 5-HT as this was 53% greater in the female than in the male hippocampi.
Abstract: Brain regional 5-hydroxytryptamine (5-HT) and/or 5-hydroxyindoleacetic acid (5-HIAA) concentrations tended to be slightly higher in female rats than in males but differences were substantial only in the hippocampus where female values were 34% and 36% higher respectively. These findings were consistent with the synthesis rates of 5-HT as this was 53% greater in the female than in the male hippocampi. Other regions did not show significant sex differences. The 5-HT[n1A] agonist 8-hydroxy-2-(di-n-propylamino) tetralin (8-OH-DPAT, 1 mg/kg sc) caused comparable decreases of 5-HT synthesis rate in both sexes and in all regions studied except the hippocampus where the percentage decrease was twice as large in the females (−64%) as in the males (−32%) so that the sex difference in 5-HT synthesis in this region largely disappeared. The results are discussed in relation to sex differences in behaviour and hippocampal function.
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TL;DR: Current human findings regarding sex differences in experimental pain indicate greater pain sensitivity among females compared with males for most pain modalities, including more recently implemented clinically relevant pain models such as temporal summation of pain and intramuscular injection of algesic substances.
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Journal Article•
TL;DR: Procedures are described for measuring protein in solution or after precipitation with acids or other agents, and for the determination of as little as 0.2 gamma of protein.
289,852 citations
Book•
01 Jan 1983
TL;DR: This paper presents a meta-analyses of the determinants of earthquake-triggered landsliding in the Czech Republic over a period of 18 months in order to establish a probabilistic framework for estimating the intensity of the earthquake.
Abstract: Preface. Acknowledgements. Introduction. References. List of Structures. Index of Abbreviations. Diagrams.
57,116 citations
"Hippocampal 5-hydroxytryptamine syn..." refers background in this paper
...9% NaC1 and the desired brain regions identified with the aid of a stereotaxic atlas (Paxinos and Watson, 1982)....
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TL;DR: It is reported that, in addition to a spatial discrimination impairment, total hippocampal lesions also cause a profound and lasting placenavigational impairment that can be dissociated from correlated motor, motivational and reinforcement aspects of the procedure.
Abstract: Electrophysiological studies have shown that single cells in the hippocampus respond during spatial learning and exploration1–4, some firing only when animals enter specific and restricted areas of a familiar environment. Deficits in spatial learning and memory are found after lesions of the hippocampus and its extrinsic fibre connections5,6 following damage to the medial septal nucleus which successfully disrupts the hippocampal theta rhythm7, and in senescent rats which also show a correlated reduction in synaptic enhancement on the perforant path input to the hippocampus8. We now report, using a novel behavioural procedure requiring search for a hidden goal, that, in addition to a spatial discrimination impairment, total hippocampal lesions also cause a profound and lasting placenavigational impairment that can be dissociated from correlated motor, motivational and reinforcement aspects of the procedure.
6,143 citations
"Hippocampal 5-hydroxytryptamine syn..." refers background in this paper
...The hippocampus is essential for the learning and remembering of spatial information (Morris et al., 1982; Barnes, 1988) and these processes may be impaired by 5-HT as injecting it into the hippocampus is reported to cause retrograde amnesia (Essman, 1978)....
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TL;DR: The distribution of serotonin-1 (5-HT1) receptors in the rat brain was studied by light microscopic quantitative autoradiography and the existence of 'selective' areas allowed a detailed pharmacological characterization of these sites to be made in a more precise manner than has been attained in membrane-binding studies.
1,866 citations
"Hippocampal 5-hydroxytryptamine syn..." refers background in this paper
...This could be because the median raphe which projects predominantly to the hippocampus (review Molliver, 1987) is poorer in 8-OHDPAT binding sites than is the dorsal raphe (Weissman-Nanopoulos et al., 1985; Pazos and Palacios, 1985) which projects mainly to other regions....
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...The lack of parallelism between 5-HT1A receptor densities in terminal regions (hippocampus > cortex, hypothalamus ~> striatum; Pazos and Palacios, 1985) and the above effects of 8-OH-DPAT (Fig....
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TL;DR: The evidence for differing rates of depression between the sexes in the United States and elsewhere during the last 40 years is reviewed, and the various explanations offered are critically analyzed.
Abstract: • This article reviews the evidence for differing rates of depression between the sexes in the United States and elsewhere during the last 40 years, and then critically analyzes the various explanations offered. These explanations include the possibility that the trends are spurious because of artifacts produced by methods of reporting symptoms, or that they are real because of biological susceptibility (possibly genetic or female endocrine), psychosocial factors such as social discrimination, or female-learned helplessness.
1,811 citations
"Hippocampal 5-hydroxytryptamine syn..." refers background in this paper
...As defective adapta t ion is a rat model of depression (review Curzon, 1988), these findings may thus be relevant to the greater incidence of the illness in women (Weissman and Klerman, 1977)....
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