A study on lympho-epithelial symbiosis in thymus; reactions on the lymphatic tissue to extracts and to implants of epithelial components of thymus.
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Lymph Nodes↗
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Biological activities of nerve growth factor bound to nitrocellulose paper by Western blotting.
We have previously developed a cell-blot technique to visualize directly in tissue extracts molecules that display the biological activity of ciliary neuronotrophic factors (CNTFs). This technique involves SDS-PAGE of the tissue extract, Western blotting on nitrocellulose paper, neuronal cell culture on the paper, and, using a vital dye, visualization of the neurons that selectively survive on the trophic factor band. In this report, we show that (1) NGF, either purified or in a crude extract from submaxillary glands, can also be successfully recognized using a slightly modified cell-blot technique; (2) a variety of ganglionic neurons can respond to distinct nitrocellulose-anchored trophic factors; (3) while CNTF and NGF can both support the survival of their common target cells, only NGF also promotes neuritic extension; and (4) both the dimeric and the monomeric forms of immobilized beta-NGF are active.
Animals↗
Catecholamine biosynthesis in vitro and in vivo in the chromaffin tissue of the Atlantic cod, Gadus morhua.
1. The biosynthesis of [3H]catecholamines from [3H]L-tyrosine in the intact chromaffin tissue of cod posterior cardinal veins was studied in vitro and in vivo at 10 degrees C. 2. The tritiated products dopamine, noradrenaline and adrenaline were separated from the [3H]tyrosine by paper chromatography of tissue extracts and the radioactivity of 1 cm strips of the chromatogram was determined by liquid scintillation spectrophotometry. DOPA could never be demonstrated in the tissue extracts from any of the experiments performed. 3. The content of [3H]noradrenaline in pieces of the cardinal veins incubated in vitro was found to increase rapidly. The tissue content of dopamine and adrenaline remained at lower levels which were reached during the first few hours of the incubation. A similar pattern could be demonstrated in the chromaffin tissue in vivo after infusion of [3H]tyrosine, but the total content of the [3H]catecholamines was lower than in the in vitro experiments. 4. The results are consistent with the view that the methylation of noradrenaline is the rate-limiting step in the biosynthesis of adrenaline in cod chromaffin tissue.
Animals↗
A comparison between microwave irradiation and decapitation: basal levels of dynorphin and enkephalin and the effect of chronic morphine treatment on dynorphin peptides.
Opioid peptides were analysed in tissue extracts of various brain structures and the pituitary gland from rats sacrificed by microwave irradiation, and compared with peptide levels in tissue extracts from decapitated rats. Dynorphin A, dynorphin B and Leu-enkephalinArg6, derived from prodynorphin, and Met-enkephalinArg6Phe7 from proenkephalin, were measured. Basal immunoreactive levels of dynorphin A and B were consistently higher in extracts from microwave-irradiated rats, whereas in these extracts immunoreactive levels of Leu-enkephalinArg6, an endogenous metabolite of dynorphin peptides, were either lower than, the same as or higher than in decapitated rats. Immunoreactive levels of Met-enkephalinArg6Phe7 were higher in microwave-irradiated rats. Effects of morphine treatment on prodynorphin peptide levels were evaluated and compared with previous findings in decapitated rats. Dynorphin immunoreactive levels were higher in the nucleus accumbens and striatum of morphine-tolerant rats than in corresponding areas in saline-treated rats. These results indicate tissue-specific metabolism of prodynorphin peptides and show that metabolism of opioid peptides occurs during the dissection procedure after decapitation of the rat even though precautions are taken to minimize degradation.
Animals↗
Detection of tenascin-C isoforms in colorectal mucosa, ulcerative colitis, carcinomas and liver metastases.
The glycoprotein tenascin-C is up-regulated in inflammatory and neoplastic diseases. Most available data on tissue tenascin-C content do not distinguish its various isoforms. We have quantified tissue tenascin-C signals in colorectal mucosa, ulcerative colitis, colorectal carcinomas and liver metastases using 5 monoclonal antibodies (MAbs) with different binding sites. Tenascin-C of tissue extracts was analyzed by a standardized Western blot technique and densitometry. As a reference MAb, K8 displayed tenascin-C tissue concentrations of 4.1 +/- 2.3 microgram/mg total protein in normal mucosa, 13.8 +/- 4.7 microgram/mg in ulcerative colitis, 28.8 +/- 14.5 microgram/mg in colorectal carcinomas and 25.6 +/- 8.9 microgram/mg in liver metastases. The optical density values per microgram protein tissue extract of the 5 MAbs reflect the levels of the corresponding tenascin-C epitopes. Various signal intensities indicate a distinct diagnostic usefulness of the MAbs in detecting colorectal carcinomas. The binding characteristics of MAb J1/tn2 point to an under-representation of the TNfnD domain in metastasizing colorectal carcinomas, while MAb 19H12 showed an increased binding rate on the TNfnA1,2,4 region. Our comparative study of tenascin-C in inflammatory and neoplastic diseases of the colon mucosa substantiates the occurrence of large differences in the diagnostic value of tenascin-C MAbs. The detected alterations of tenascin-C in metastasizing colorectal carcinomas might indicate a prognostic value of specific tenascin-C isoforms.
Antibodies, Monoclonal↗
Parallel purification of three catalytic subunits of the protein serine/threonine phosphatase 2A family (PP2A(C), PP4(C), and PP6(C)) and analysis of the interaction of PP2A(C) with alpha4 protein.
The protein serine/threonine phosphatase (PP) type 2A family consists of three members: PP2A, PP4, and PP6. Specific rabbit and sheep antibodies corresponding to each catalytic subunit, as well as a rabbit antibody recognizing all three subunits, were utilized to examine the expression of these enzymes in select rat tissue extracts. PP2A, PP4, and PP6 catalytic subunits (PP2A(C), PP4(C), and PP6(C), respectively) were detected in all rat tissue extracts examined and exhibited some differences in their levels of expression. The expression of alpha4, an interacting protein for PP2A family members that may function downstream of the target of rapamycin (Tor), was also examined using specific alpha4 sheep antibodies. Like the phosphatase catalytic subunits, alpha4 was ubiquitously expressed with particularly high levels in the brain and thymus. All three PP2A family members, but not alpha4, bound to the phosphatase affinity resin microcystin-Sepharose. The phosphatase catalytic subunits were purified to apparent homogeneity (PP2A(C) and PP4(C)) or near homogeneity (PP6(C)) from bovine testes soluble extracts following ethanol precipitation and protein extraction. In contrast to PP2A(C), PP4(C) and PP6(C) exhibited relatively low phosphatase activity towards several substrates. Purified PP2A(C) and native PP2A in cellular extracts bound to GST-alpha4, and co-immunoprecipitated with endogenous alpha4 and ectopically expressed myc-tagged alpha4. The interaction of PP2A(C) with alpha4 was unaffected by rapamycin treatment of mammalian cells; however, protein serine/threonine phosphatase inhibitors such as okadaic acid and microcystin-LR disrupted the alpha4/PP2A complex. Together, these findings increase our understanding of the biochemistry of alpha4/phosphatase complexes and suggest that the alpha4 binding site within PP2A may include the phosphatase catalytic domain.
Adaptor Proteins, Signal Transducing↗
Relative overexpression of the parathyroid hormone-related protein gene in human leiomyomas.
Uterine leiomyomas or fibroids are common among women of reproductive age, but their biology is poorly understood. The PTH-related protein (PTHrP) has been identified in a number of sites throughout the reproductive tract. We, therefore, examined whether fibroids express PTHrP mRNA and compared their level of expression with that in normal myometrium. Total RNA prepared from fibroid tissue and corresponding normal myometrium from seven patients was examined by RNase protection analysis. In all cases, fibroid and myometrial tissue expressed PTHrP, and in six of seven cases, PTHrP expression was higher in fibroids than in normal myometrium. Cultured fibroid cells from four patients also expressed higher levels of PTHrP mRNA than corresponding cultured normal myometrial cells. Tissue extracts from eight patients and conditioned medium from cultured cells from nine patients were examined for PTHrP immunoreactivity using a two-site immunoradiometric assay. In tissue extracts and conditioned medium, the mean PTHrP concentration was significantly higher in fibroids than normal myometrium. Immunohistochemical staining of fibroid and myometrial tissue was positive for PTHrP. Finally, PTHrP-(1-34) induced a dose-dependent increase in cAMP in fibroid and myometrial cells in vitro. These findings suggest that PTHrP may have an autocrine/paracrine function in regulating myometrial physiology and may play a role in regulating fibroid growth or differentiation.
Cyclic AMP↗
Structural characterization of cardiac protein phosphatase with a monoclonal antibody. Evidence that the Mr = 38,000 phosphatase is the catalytic subunit of the native enzyme(s).
The native structures of protein phosphatases have not been clearly established. Several tissues contain high molecular weight enzymes which are converted to active species of Mr approximately 35,000 by denaturing treatments or partial proteolysis. We have used a monoclonal antibody directed against purified bovine cardiac Mr = 38,000 protein phosphatase to determine whether this species is the native catalytic subunit or a proteolytic product of a larger polypeptide. Monoclonal antibody was obtained from a cloned hybrid cell line produced by the fusion of Sp2 myeloma cells with spleen cells from a mouse immunized with phosphatase coupled to hemocyanin. This antibody was specific for the Mr = 38,000 phosphatase as determined by immunoblot analysis of purified enzyme or cardiac tissue extracts after native or sodium dodecyl sulfate-polyacrylamide gel electrophoresis. A single immunoreactive protein of Mr = 38,000 was present in cardiac tissue extracts including extracts prepared from freeze-clamped rat heart rapidly denatured in hot sodium dodecyl sulfate buffer. Precipitation of cardiac extract with 80% ethanol did not alter the Mr of the phosphatase nor did it liberate new immunoreactive material not observed in the extract. Ethanol precipitation caused the dissociation of both phosphatase activity and immunoreactivity from a high Mr form to a form of Mr between 30,000 and 40,000. An immunoreactive protein of Mr = 38,000 was identified in several bovine and rat tissues as well as tissues from rabbits, mice and chickens and human HT-29 cells. From these data we conclude that the Mr = 38,000 cardiac phosphatase is a native catalytic subunit of higher molecular complexes which are dissociated by ethanol precipitation. A very similar, or identical, protein is present in several tissues and species suggesting that this catalytic subunit is a ubiquitous enzyme important in many dephosphorylation reactions.
Animals↗
Design and characterization of a metalloproteinase inhibitor-tethered resin for the detection of active MMPs in biological samples.
Matrix metalloproteinases (MMPs), zinc-dependent endopeptidases, are implicated in tumor progression. We describe herein the development of a resin-immobilized, broad-spectrum synthetic MMP inhibitor for selective binding of the active forms of MMPs from different experimental samples. We confirmed the activity-based binding of MMPs to the inhibitor-tethered resin with purified human recombinant MMP-2, -9, and -14, samples of cultured cells, and tissue extracts. Our results show that only the free active MMPs, and not the zymogens or MMP/TIMP (enzyme-protein inhibitor) complexes, bound specifically to the resin. In our comparison of benign and carcinoma tissue extracts, we detected active MMP-2 and MMP-14 forms only in the cancerous tissue samples, indicating that a pool of the tumor MMPs is free of endogenous inhibitors (TIMPs), and is thus likely to contribute to proteolytic events that precipitate tumor metastasis.
Breast Neoplasms↗
Quantitation and potential function of nucleolar phosphoprotein pp 105 in mouse tumor cells, embryonic cells and normal tissues.
1. Nucleolar phosphoprotein pp 105 was determined in various mouse cell and tissue extracts using a highly sensitive ELISA. The results indicate that the highest relative amounts of pp 105 correlate with cells and tissues of high growth rate such as tumor cell lines, solid tumors and embryonic tissues. 2. The specific phosphorylation of pp 105 was compared in a 1 min endogenous phosphorylation assay with native cell and tissue extracts. 3. The mitogenic activity of highly purified pp 105 was demonstrated in cultures of resting mouse embryonic cells and mouse thymocytes.
Animals↗
Increased myocardial matrix metalloproteinases in hypoxic newborn pigs during resuscitation: effects of oxygen and carbon dioxide.
BACKGROUND: Perinatal asphyxia is associated with cardiac dysfunction, and it is important to prevent further tissue injury during resuscitation. There is increasing evidence that myocardial matrix metalloproteinases (MMPs) are involved in myocardial hypoxaemia-reoxygenation injury. OBJECTIVE: To assess MMPs and antioxidant capacity in newborn pigs after global ischaemia and subsequent resuscitation with ambient air or 100% O(2) at different PaCO(2)-levels. METHODS: Newborn pigs (12-36 h of age) were resuscitated for 30 min by ventilation with 21% or 100% O(2) at different PaCO(2) levels after a hypoxic insult, and thereafter observed for 150 min. In myocardial tissue extracts, MMPs were analyzed by gelatin zymography and broad matrix-degrading capacity (total MMP). Total endogenous antioxidant capacity in myocardial tissue extracts was measured by the oxygen radical absorbance capacity (ORAC) assay. RESULTS: Matrix metalloproteinase-2 more than doubled from baseline values (P < 0.001), and was higher in piglets resuscitated with 100% O(2) than with ambient air (P = 0.012). The ORAC value was considerably decreased (P < 0.001). In piglets with elevated PaCO(2), total MMP-activity in the right ventricle was more increased than in the left ventricle (P = 0.008). In the left ventricle, total MMPactivity was higher in the piglets with low PaCO(2) than in the piglets with elevated PaCO(2) (P = 0.013). CONCLUSION: In hypoxaemia-reoxygenation injury the MMP-2 level was highly increased and was most elevated in the piglets resuscitated with 100% O(2). Antioxidant capacity was considerably decreased. Assessed by total MMP-activity, elevated PaCO(2) during resuscitation might protect the left ventricle, and probably increase right ventricle injury of the myocardium.
Animals↗
Prognostic impact of urokinase-type plasminogen activator and its inhibitor PAI-1 in completely resected gastric cancer.
The prognostic impact of the proteolytic factors urokinase-type plasminogen activator (uPA) and plasminogen activator inhibitor type 1 (PAI-1) was evaluated in 76 completely resected gastric cancer patients enrolled in a prospective study. All patients underwent macroscopically and microscopically residual tumor-free resection (category R0, Union International Contre Cancer, 1987). uPA and PAI-1 levels were quantified in detergent-extracted (Triton X-100) specimens of primary gastric tumors by enzyme-linked immunosorbent assays. Median values of 1.57 ng uPA/mg protein were determined in tumor tissue extracts compared to 0.14 ng uPA/mg protein in normal mucosa. For PAI-1, 0.93 ng PAI-1/mg protein versus 0.09 ng PAI-1/mg protein was calculated. uPA levels in tumor tissue extracts were significantly correlated with vascular invasion, Laurén classification, and WHO classification, whereas PAI-1 levels showed a significant correlation with advanced lymph node involvement, depth of invasion, tumor stage, site of tumor, and the Laurén, Borrmann, and WHO classifications. Elevated uPA and PAI-1 levels were found to be associated with poor prognosis. The optimal cutoff values indicating a group of patients with shorter survival were 1.5 ng uPA/mg protein and 1.25 ng PAI-1/mg protein, respectively (Classification and Regression Tree analysis). Patients with either high uPA or PAI-1 values were significantly associated with decreased survival (median time of survival was 23 months (high) versus 44 months (low). By univariate Cox regression analysis, it was shown that TNM categories, WHO classification, size of tumor, uPA and PAI-1 levels were all significantly associated with survival. However, in multivariate Cox regression analysis of these grouped variables, nodal status, PAI-1 levels, and WHO classification were the only independent prognostic factors. The relative risks of failure were 5-, 2.9-, and 2.4-fold, respectively. We conclude that PAI-1 and uPA positivity may serve as new prognostic factors in gastric cancer, predicting shorter survival even in clinically important subgroups of patients.
Adult↗
Enhanced glutathione S-transferase (GST) activity in pregnant rats treated with benzo(a)pyrene.
Administration of Benzo(a)pyrene (BP, 50 mg/kg/d) to pregnant rats significantly increased Glutathione S-transferase (GST) activity in placental tissue-extract (Vmax = 40 nmol/min/mg protein and 69 nmol/min/mg protein in controls versus treated animals respectively; P less than 0.01) and total fetal tissue-extract (Vmax = 51 nmol/min/mg protein and 82 nmol/min/mg protein in controls versus treated animals respectively; P less than 0.01) indicating an induction effect of BP on the GST system. An increase in the Km values was also observed: 1.61 x 10(-3) M and 2.84 x 10(-3) M in control versus treated placentae; 1.38 x 10(-3) M and 2.05 x 10(-3) M in control versus treated fetuses. A competitive effect on the enzyme by the BP present in the sample may also be involved. The glutathione content in both tissues did not show any changes after the treatment with BP. This increase in the GST system was not sufficient to protect the fetus. BP affected the reproductive performance of pregnant rats by significantly increasing the number of resorptions and fetal wastage, and, also, by decreasing the fetal weight.
Animals↗
Insulin action in intact mouse diaphragm. I. Activation of glycogen synthase through stimulation of sugar transport and phosphorylation.
The incubation of intact mouse diaphragms with insulin caused a dose and time dependent increase in the independent activity of glycogen synthase in tissue extracts. 2-deoxyglucose (2-10 mM) alone markedly stimulated the conversion of glycogen synthase to the independent activity under conditions in which tissue ATP concentrations were not affected. The incubation of diaphragms with both insulin and 2-deoxyglucose resulted in a greater than additive effect. Insulin stimulated the uptake of 2-deoxyglucose into mouse diaphragms, accumulating as 2-deoxyglucose-6-phosphate. The accumulation of 2-deoxyglucose-6-phosphate correlated well with the increase in the independent activity of glycogen synthase and with the activation of glycogen synthase phosphatase in tissue extracts. The uptake of 3-0 methyl glucose was also markedly stimulated by insulin, without affecting the activity of glycogen synthase. Both glucose-6-phosphate and 2-deoxyglucose-6-phosphate stimulated the activation of endogenous glycogen synthase phosphatase activity in muscle homogenates. We conclude that insulin, in addition to its effects in the absence of exogenous sugars, increases the independent activity of glycogen synthase through increased sugar transport resulting in increased concentrations of sugar-phosphates which promote the activity of glycogen synthase phosphatase.
Adenosine Triphosphate↗
Cathepsin B, thiols and cysteine protease inhibitors in squamous-cell lung cancer.
We investigated activities of the cysteine protease cathepsin B (CB; EC 3.4.22.1), the levels of reduced glutathione (GSH) and cysteine and the activity of gamma-glutamyltransferase (gamma-GT; EC 2.3.2.2) in squamous-cell lung carcinoma (SQCLC) and the lung parenchyma specimens from surgically treated patients. The basal CB activity, assayed in tissue extracts in the absence of exogenous activators, was significantly higher in SQCLC compared to the lung. The residual CB activity, remaining in tissue extracts after preincubation at 37 degrees C, was not any longer significantly different in SQCLC and the lungs. The inhibited CB activity, calculated as the difference between the basal and residual CB activities, was significantly higher in SQCLC compared to the lung. In the case of the cysteine protease cathepsin C (CC; EC 3.4.14.1), neither the basal nor the residual nor the inhibited CC activities in SQCLC and the lung were significantly different. Compared to CC, the powerfulness of endogenous cysteine protease inhibitors to inhibit CB was much higher in both SQCLC and the lung. The cysteine protease inhibitors from SQCLC and the lung which effectively inhibited CB could be related to the inhibitors with an apparent M(r) ranging from 10,000 to 30,000. Isoelectric focusing studies indicated significant differences in the progress of inhibition of the activity of CB isoforms in SQCLC and lung parenchyma extracts. The levels of both GSH and Cys were significantly higher in SQCLC compared to the lung and the level of GSH was significantly higher in Stage III tumors compared to Stage I tumors. The activity of gamma-GT was not significantly different in SQCLC and the lung but it was significantly higher in Stage I tumors compared to Stage III tumors and showed a significant negative correlation with GSH level in SQCLC. Dithiothreitol did not increase the basal activity of CB from SQCLC and the lung which indicates that reversibly oxidized forms of CB do not accumulate in the tumors and the lungs. The basal activity of CB from SQCLC and the lung was competitively inhibited by Cys. Moreover, increasing Cys concentrations had a modulatory effect on the basal activity of CB from SQCLC and the lung which was featured by Cys-induced inhibition of CB activity and by subsequent Cys-effected recovery of CB activity from its previous inhibition by Cys.
Adult↗
Tissue and plasma levels of immunoreactive gastrin and cholecystokinin in chickens with and without bombesin.
Immunoreactive gastrin and immunoreactive cholecystokinin were measured in chicken tissue extracts obtained from the gut and brain. In contrast to that found in mammals, immunoreactive gastrin found in chickens was higher in the brain than in gut tissues, and it was highest in the ileum when compared with other gut tissues. Dose-response curves of tissue extracts from the brain and ileum and of serum were parallel to the dose-response curve of synthetic human gastrin, suggesting the existence of gastrin or a peptide immunologically similar to gastrin in those chicken tissues. Immunoreactive cholecystokinin in tissues was highest in the duodenum, followed by the jejunum, ileum, and cortex; lesser amounts of cholecystokinin were found in other tissues. Influence of bombesin on the release of immunoreactive gastrin and immunoreactive cholecystokinin in the blood of chickens was also studied. Bombesin doses of 3 micrograms/kg per hour significantly increased immunoreactive gastrin in serum and immunoreactive cholecystokinin in plasma, whereas gastrin did not increase with a bombesin dose of 0.6 micrograms/kg per hour. The results confirm the existence of immunoreactive gastrin and immunoreactive cholecystokinin in the tissue of chickens and indicate that they are released into circulation in response to bombesin.
Animals↗
Adrenergic vasoconstriction augments tissue O2 extraction during reductions in O2 delivery.
When systemic O2 delivery is reduced, increases in systemic O2 extraction are facilitated by sympathetically mediated increases in vascular resistance that limit blood flow to regions with low metabolic demand. Local metabolic vasodilation competes with this vasoconstriction, thereby effecting a balance between tissue O2 supply and demand. This study examined the role of sympathetically mediated vasoconstriction on the critical level of O2 extraction in hindlimb and whole body during progressive reductions in O2 delivery. In anesthetized dogs, the left hindlimb was vascularly isolated and its O2 delivery was decreased in stages by reducing the speed of an occlusive pump. In a normovolemic group (n = 6), blood volume was maintained to minimize sympathetic tone while flow to the hindlimb was reduced. In a hypovolemic group (n = 6), blood volume was removed in stages to augment sympathetic tone progressively while flow to the limb was reduced simultaneously. A phenoxybenzamine group (n = 6) was identical to the hypovolemic group, except that alpha-adrenergic effects were inhibited with phenoxybenzamine (3 mg/kg). The systemic critical O2 extraction ratio in the phenoxybenzamine group (0.60 +/- 0.06) was less than for the hypovolemic group (0.71 +/- 0.04; P = 0.004). In the hindlimb, critical O2 extractions were significantly less in the normovolemic (0.46 +/- 0.17) and phenoxybenzamine (0.49 +/- 0.10) groups compared with the hypovolemic group (0.72 +/- 0.10; P < or = 0.008).(ABSTRACT TRUNCATED AT 250 WORDS)
Acid-Base Equilibrium↗
In vivo studies on the basal and evoked release of cholecystokinin and vasoactive intestinal polypeptide from cat cerebral cortex and periventricular structures.
In cat, radioimmunoassay revealed high concentrations of vasoactive intestinal polypeptide (VIP) and cholecystokinin (CCK) (approximately 10-90 ng/g wet weight tissue) in various regions of the cerebral cortex and in periventricular structures. Superfusion of cat cerebral cortex or perfusion from the lateral ventricle to the cisterna magna with artificial cerebrospinal fluid (CSF) was carried out in cats anesthetized with chloralose-urethane. The superfusate was assayed for VIP- and CCK-like immunoreactivity (VIP-LI and CCK-LI) simultaneously. Basal efflux of VIP-LI was 13.8 +/- 4.1 fmol/30 min/cm2 cortex and 31.6 +/- 5.0 fmol/30 min in ventriculo-cisternal superfusate. Basal efflux of CCK-LI, assayed in the same superfusate sample, was 10.7 +/- 2.5 fmol/30/min/cm2 cortex in cortical cup superfusate and 25.6 +/- 4.4 fmol/30 min in ventriculo-cisternal superfusate. The addition of potassium (50 mM) and veratridine (7.5 X 10(-5) M) to the superfusate produced significant increases in the levels of VIP-LI in both ventricular and cortical effluents. The potassium evoked release of VIP-LI and CCK-LI was inhibited by the substitution of cobalt (4 mM) for the calcium ion in the perfusion media; basal efflux was not affected. Separation of immunoreactivity by gel filtration chromatography demonstrated the CCK-LI in cat cortical tissue co-chromatographed with the COOH-terminal 4, 8, 33 and 39 amino acid peptide fragments of CCK and with a larger molecule. In contrast, the immunoreactivity in cortical and ventricular superfusate obtained during basal and evoked release co-migrated with authentic CCK octapeptide. For VIP, all immunoreactivity in tissue extract of cerebral cortex existed as a single peak which co-migrated with authentic VIP-28. The molecular pattern in cortical superfusate corresponded to that found in tissue extract.
Animals↗