WGA-HRP was iontophoretically delivered into the habenular nuclei in 40 rats to observe the distribution of the retrograde labeled cells; and into the entopeduncular nucleus(EPN), lateral preoptic area(LPO), medial preoptic area(MPO), nucleus septalis fimbriatis(SF), nucleus triangularis septi(TS), nucleus tractus diagonalis (Broca)(DBN)and lateral hypothalamic area(LHA) in 12 rats to observe the distribution of the orthograde labeled fibers in the habenular nuclei. It was found that the afferents of various parts of the habenular nuclei were different.The lateral habenular nucleus mainly recieves the afferents from the EPN, LPO and LHA, and the medial habenular nucleus from the SF, TS and LHA. Furthermore, the lateral habenular nucleus can be divided into medial and lateral parts, the medial habenular nucleus can be divided into medial and lateral parts as well, their afferent connections are also different.

WGA-HRP was iontophoretically delivered into various parts of the habenular nuclei (the lateral segment of the lateral habenular nucleus LHb-L, the medial segment of the lateral habenular nucleus LHb-M, and the medial habenular nucleus MHb) in 40 rats to study the route and distribution of the anterograde labeled fibers and terminals in the brain. The efferent projections of the habenular nuclei follow three routes, the rostral, contralateral and caudal pathways. Along the rostral pathway fibers leave the lateral habenular nucleus, follow the stria medullaris thalami rostrally, and distribute to the thalamic dorsomedial nucleus, paratenial nucleus and lateral preoptic area. Fibers from the contralateral pathway distribute to the opposite lateral habenular nucleus by way of the commissura habenularum Fibers in the caudal pathway originate mainly from the MHb and LHb-M, and distribute to the interpeduncular nucleus with a dorsoventral topographic localization. In addition some of the caudal efferent fibers run caudally and terminate in the raphe nuclei and reticular formation etc.

WGA-HRP was injected into the dorsal part of anterior cingulate area,prelim- bic area,and dorsal agranular insular area of the prefrontal cortex in 25 rats to observe the afferent connections from the diencephalon and subcortical telencephalon. The afferent projections from the diencephalon mainly originate from the dorsome- dial nucleus of the thalamus,and some topographic localization may exist.Further- more,the afferent projections to the prefrontal cortex arise from the thalamic intralaminar nuclei(centrolateral nucleus,paracentral nucleus,centromedial nucleus and parafascicular nucleus),the ventral thalamic nuclei(ventrolateral nucleus,ven- tromedial nucleus,ventroanterior nucleus and ventroposterior nucleus),the midline nuclei(rhomboid nucleus,reuniens nucleus,paratenial nucleus,and paraventricular nucleus of the thalamus),the anteromedial nucleus,the lateral habenular nucleus, the posterior nucleus of the thalamus,and the lateral nucleus of the thalamus.The numbers projecting to the prefrontal cortex were different in different thalamic nuclei.The afferent projections from the hypothalamus mainly originate from the lateral hypothalamic area,lateral preoptic area,caudal magnocellular nucleus,and supramamillary nucleus.A few of afferent projections from the posterior hypothala- mic area,dorsomedial and ventromedial nucleus of the hypothalamus and zona inserta were also observed.The afferent projections from the subcortical telence- phalon mainly originate from the globus pallidus,the diagonal band nucleus,the septal nuclei(medial septal nucleus,lateral septal nucleus,septofimbrial nucleus and nucleus triangularis septi),the amygdaloid nuclei(lateral amygdaloid nucleus,lateral and medial part of basal amygdaloid nucleus,medial amygdaloid nucleus and cortical amygdaloid nucleus)and the claustrum.

Using immunohistochemical method, the distribution of eight kinds of peptidergic neurons, i. e. cholecystokinin(CCK),vasoactive intestinal polypeptide (VIP), substance P(SP), neurotensin (NT), galanin (GAL), calcitonin gene-related peptide (CGRP), corticotropin-releasing factor(CRF) and thyrotropin-releasing hormone(TRH), of the thalamus in the rat was investigated. Immunoreactive cell bodies and fiber terminals were mainly located in the midline nuclei, intralaminar nuclei, habenular nucleus and posterior nuclei of the thalamus, but a few of positive structures in the anterior nuclei, ventral nuclei and reticular nucleus were also found. The distribution of different peptidergic neurons in the thalamus was different from each other. A large quantity of SP-, NT- and GAL- like cell bodies and all of above-mentioned eight peptidergic fiber terminals were observed in the midline nuclei and intralaminar nuclei. More CCK and CGRP positive cell bodies were seen in the posterior nuclei. Some VIP, SP, NT, GAL and CRF positive cell bodies and all kinds of the positive terminals, except CGRP, were found in the habenular nucleus. The immunoreactive structures which were found in present study, particularly the distribution of positive terminals, were more widely than those were reported. The distribution of some CCK, VIP, NT, GAL, CGRP and TRH positive cell bodies and terminals in the thalamus have not been reported previously.

Aging changes of neurotensin-like (NT-L) and galanin-like (GAL-L) cell bodies and fiber terminals in the central amygdaloid nucleus between the young and old rats were studied by means of immunohistochemical and microspectrophotometric techniques. NT-L cell bodies were mainly located in the central part (CeLn) of, centrolateral amygdaloid nucleus, a few of NT-L neurons were also found in the centrolateral amygdaloid nucleus, capsular part (CeLc) and centromedial amygdaloid nucleus (CeM). NT-L fiber terminals were seen mainly in the CeLn and CeLc. GAL-L cell bodies were observed only in the CeM. A marked decrease of density of NT-L cell bodies and fiber terminals in the central amygdaloid nucleus was found in the old rats as compared with young animals. No significant age difference in number of GAL-L cell bodies was observed in the central amygdaloid nucleus, but the staining intensity of GAL-L cell bodies was reduced remarkably. The results show that there are apparent changes with aging of the NT-L and GAL-L neurons in the central amygdaloid nucleus of the rat. The significance of the changes remains to be studied further.

The short chain fatty acids inplatelet concentrate (PC) and serumwere determined by means of gaschromatography.The short chainfatty acids determined includeacetic,propionic,butyric,isobuty-ric,valeric,isovaleric,lactic,pyruvic and succinic acids.Therewere acetic,lactic,pyruvic andsuceinic acids in PC;their relativecontents were 1.14,13.50,1.41 and9.54,respectively.The serum cont-ained acetic,lactic and pyruvic aci-ds;their relative contents were0.98,4.33 and 1.88,respectively.Succinic acid wasn't found in theserum,suggesting that the succinicacid in PC is the content of platelets.There was a positive correlationbetween the platelet count and lacticacid content of PC.Fresh PC wascompared with the PC of same volumepreserved for 0,24,48,72 hours atroom temperature.The lactic acidcontent of PC increased with thetime of preservation.

0.02～0.3?l of 33％ HRP (Sigma Ⅵ) solution in sterile water were injected with a stereotaxic instrument into various sites of the caudate-putamen in 40 rats. The animals were perfused transaortically with 3％ paraformatdehyde and 1％ glutaradehyde in 0.1 M phosphate buffer solution (pH7.4). Frozen sections were dried in a container with P_2O_5 for 2～4 hours and examined for fluorescence in the nucleus nigra. After which, the sections were processed for HRP reaction according to Mesulam's method. A number of cells of substantia nigra were found to show both fluorescence and HRP-positive product, thus confirming the dopaminergic nature of the nigroneostiatum projection.Furthermore, the nigroneostriatum projection was found to be topographically organized, the ventro-medial part of compact zone of the substantia nigra projecting to the dorso-medial caudate-putamen, the dorso-medial part of compact zone to the ventral caudate-putamen, the ventro-middle of compact zone to 1be dorso-lateral and central caudate-putamen, the caudo-lateral part to the central caudate-putamen, the middle part of reticular zone to the lateral and central caudate-putamen, the lateral zone of substantia nigra to the caudal caudate-putamen. Some overlap existed.Strionigral fibers were also topographically organized, which terminated predominantly about the cells of reticular zone. These may form a feedback loop concerning with the modulation of the activity of the dopaminergic neurons in the substantia nigra.

Different fluorescent tracers, Fast Blue (FB), Nuclear Yellow(NY), Propidium iodide (PI), Bisbenzimide (Bb), Evans Blue(EB), DAPI-Primuline (Pr), were injected into the frontal cortex, hippocampus, thalamus, cerebellum and cervical cord respectively in 31 rats to observe the fluorescent retrograde double labeling cells in the nucleus raphe magnus. The results showed that the axon collaterals of the nucleus raphe magnus projected to the :thalamus-cerebellum, thalamus-hippocampus, frontal cortex-thalamus, frontal cortex-cerebellum, hippocampus-cerebellum, hippocampus-cervical cord, cerebellum-cervical cord, thalamus-cervical cord and bilateral hippocampus and thalamus. The topographical organizations of divergent projection neurons of the nucleus raphe magnus were also found.

WGA-HRP was injected into different segment of the dorsomedial nucleus (DM) of thalamus by means of microiontophoretical delivery in 19 rats to observe the afferent projections of DM. It is found that the DM received afferent projections widely from the frontal cortex, basal telecephalon, limbic system, monoaminergic neuron, reticular formation, central gray matter and superior colliculus. Furthermore, some topographical organization has also been observed. The medial segment of DM received afferent projections mainly from dorsal agranular insular cortex, infralimbic cortex, amygdaloid complex, septum, bed nucleus of the stria terminalis and raphe nuclei, related with the function of the limbic system. The central segment of DM received afferent projections from the dorsal agranular insular cortex and the prepiriform cortex, also related with the function of the limbic system. The lateral segment of DM received afferent projections mainly from the medial precentral cortex, dorsal division of anterior cingulate cortex, E-W nucleus and superior colliculus, related with the function of eye movement. In addition, all the three segments of DM received numerous afferents from the substantia innominata, nucleus tractus diagonalis (Broca), lateral preoptic area and reticular nucleus of the thalamus.

The horseradish peroxidase tracing method was used to investigate the thalamostriate projections in the rat. Following the caudoputamen injections, numerous labeled neurons were present in the intralaminar nuclei of the thalamus. HRP-positive cells were found mainly in the central lateral nucleus following the injections of the medial portion of the caudoputamen, and in the paracentral nucleus following the injections of the lateral portion of the caudoputamen. Besides the intralaminar nuclei, however, considerable amount of labeled neurons were found in other tbalamic nuclei as well, including the ventral anterior, ventral lateral and ventral medial nuclei of the thalamus. In addition, a few labeled cells were also found in the dorso medial, anterior dorsal, anterior ventral, and anterior medial thalamic nuclei.