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A Coquerel

Publications and source records attributed to A Coquerel.

At least 19 recordsLinked to original sources
PubMed2006

[Acute renal failure with acyclovir in a 42-year-old patient without previous renal dysfunction].

INTRODUCTION: Herpetic meningoencephalitis is treated with acyclovir (15 mg/kg/8 h). This higher dosage enhance the risk of acute renal failure. CASE REPORT: We report the case of a previously healthy 42 years old man treated by intravenous aciclovir 1g/8 h for a herpetic meningoencephalitis. He presented an acute renal failure and an acute confusional state at the end of the treatment. Renal function and neurologic status improved rapidly with increased hydration and stop of the antiviral therapy. CONCLUSION: If acyclovir is usually well tolerated, there is also a risk of acute nephropathy, especially dose-dependent. We point out the need to monitor renal function when high dosage of acyclovir is indicated.

Acute Kidney Injury↗
PubMed2005

Concentration of neuron-specific enolase and S100 protein in the subretinal fluid of rhegmatogenous retinal detachment.

BACKGROUND: Neuron-specific enolase and S100 protein are markers of neuronal lysis. To assess the neuronal suffering in rhegmatogenous retinal detachment we quantified neuron-specific enolase and S100 protein in the subretinal fluid. METHODS: The puncture was performed in the sclera with a Merseture 5/0 round needle, and the fluid was collected with a glass capillary tube. Twelve subretinal fluid samples were obtained from 12 eyes with rhegmatogenous retinal detachment undergoing retinal detachment surgery. Vitreous from ten eyes with macular hole or epimacular membrane served as negative control group, and vitreous collected during cornea procurement from ten deceased patients served as positive control group. RESULTS: The mean concentration of neuron-specific enolase (in nanogrammes per millilitre) was 602 in the subretinal fluid of rhegmatogenous retinal detachment, 10.2 in the serum of these patients, 2.9 in the vitreous of the negative control group, and 364 in the positive control group. The mean concentration of S100 protein (in nanogrammes per millilitre) was 104 in the subretinal fluid of rhegmatogenous retinal detachment, <0.1 in the serum of these patients and in the vitreous of the control negative group, and 11.18 in the positive control group. CONCLUSION: Neuron-specific enolase (NSE) and S100 are known to be good markers of brain stress and, thus, are good markers of retinal stress.

Adult↗
PubMed2005

Pharmacokinetics of mycophenolic acid in kidney transplant patients receiving sirolimus versus cyclosporine.

INTRODUCTION: Mycophenolic acid (MPA) pharmacokinetics exhibit large variability in transplant recipients and may be altered due to concurrent immunosuppressants. Little is known about the influence of sirolimus (SRL) on MPA pharmacokinetics in kidney transplant patients. METHODS: We studied the areas under concentration-time curves (AUC) for MPA in 15 patients receiving immunosuppression combining SRL with mycophenolate mofetil (MMF). The pharmacokinetic measurements were performed in all patients using three MMF dosing regimens (0.5 g twice a day, 0.75 g twice a day, 1 g twice a day). Similar blood AUC profiles were also sampled from 12 patients treated with a fixed dose of MMF 1 g twice a day and cyclosporine (CsA). MPA was measured using HPLC; the AUC0-12 of MPA was determined by the trapezoidal method using four sampling time points: C0, C1, C3, C5. RESULTS: While patients on SRL were receiving 0.75 g MMF twice a day, mean AUC0-12 and C0 values of MPA were comparable to those of patients receiving CsA and 1 g MMF twice a day (54.1 +/- 17.6 and 3 +/- 1.87 vs 51.7 +/- 16.7 mg.h/L and 2.76 +/- 1.57 mg/L, respectively). On the other hand, 0.5 g MMF twice a day with SRL therapy resulted in AUC0-12 and C0 values of MPA of 32.3 +/- 12.6 mg.h/L and 2.32 +/- 1.72 mg/L, respectively, whereas, 1 g MMF twice a day with SRL resulted in AUC0-12 and C0 values of MPA of 70.9 +/- 19.3 mg.h/L and 4.7 +/- 2.44 mg/L, respectively. CONCLUSIONS: These findings demonstrate that MPA exposure in the presence of SRL is higher than that with CsA. It appears that the MMF dose should be reduced to 0.75 g twice a day in patients receiving SRL to obtain AUC0-12 of MPA levels comparable to that in patients treated with CsA and MMF 1 g twice a day.

Area Under Curve↗
PubMed2005

Serum erythropoietin levels in septic shock.

Erythropoietin is a glycoprotein hormone mainly released by the kidney, which stimulates red blood cell production. However, in sepsis, the mechanisms responsible for the final increase in circulating erythropoietin remain unclear Seventeen critically ill patients with Simplified Acute Physiologic Score average 66 (range 43 to 103) were included in this study. Ten patients survived and seven died within 28 days. Blood samples obtained at different times were assayed for erythropoietin, cytokine levels and lactate measurements. PCO2 gap was assessed to detect the presence of gastric mucosal acidosis. Erythropoietin decreased in the patients who survived while it remained high or increased in non-survivors (37+/-6.5 vs 147+/-6. 7 UI/l respectively, P<0.05). Erythropoietin plasma levels were correlated with IL-6 levels (r=0.84, P<0.05) and TNFalpha levels (r=0.84, P<0.05). We observed a significant positive relationship between erythropoietin plasma levels and lactate concentrations (r= 0.89, P< 0. 05) and with PCO2 gap (r=0.9, P < 0.05). No correlation was found between erythropoietin concentration and the other parameters. High serum erythropoietin levels in non-survivors were observed with septic shock despite an increase in the levels of proinflammatory cytokines. We found a relationship between erythropoietin concentration and biological markers of tissue hypoperfusion i.e. lactate levels or PCO2 gap. This relationship could suggest tissue hypoperfusion as the stimulating factor for erythropoietin production in septic shock.

Adult↗
PubMed2003

Short-term pharmacokinetics and brain distribution of mecamylamine as a preliminary to carbon-11 labeling for nicotinic receptor investigation.

As a preliminary to development and evaluation of labeled mecamylamine as a potential in vivo imaging ligand for human central nicotinic receptors (nAchRs), this work was intended to determine whether the pharmacokinetic properties of mecamylamine are suitable for experimental studies using (11)C-radiolabeled mecamylamine preliminary to positron emission tomography (PET) in humans. An original gas chromatographic method for rapid and simple determination of mecamylamine in biological samples was developed and validated (within run precision, 3.8-5.2%; between assay variation, 5.3-6.9%; assay accuracy, 5.6-11.8%). The results of the pharmacokinetic investigation in the rat demonstrated a very fast clearance of mecamylamine from blood [half-life, 1.2 h; clearance (CL), 1.2 L/kg/h) concomitant with an uptake that was higher in kidney, intermediate in lung, and lower in heart, liver, and brain. Brain tissue kinetics of mecamylamine showed a similar pattern for all the regions, with a rapid increase followed by a plateau after 15 min. This plateau differed according to the region of the brain; it was higher in colliculi, hippocampus, and cortex (area of high density of nAchRs) than in cerebellum or white matter (area with a limited population of nAchRs). No other lipophilic metabolites that were able to disturb the specific binding to nAchRs were identified during the investigation. Thus, mecamylamine shows peculiar qualities making it a good candidate for carbon-11 labeling for experimental studies in view of final PET imaging.

Animals↗
PubMed2001

Localization of neurotensin NTS2 receptors in rat brain, using.

The brain localization of the neurotensin receptor NTS2 was studied with [3H]levocabastine, using an autoradiographic procedure. This study suggests that NTS2 receptors are mainly intracellular. High densities of binding sites were observed in the cingulate, insular, temporal, occipital, enthorhinal cortex, amygdaloid complex, septohippocampal nuclei, medial thalamus, mammillary bodies and superior colliculi; a moderate labelling was observed in the anterior and medial hippocampus, olfactory tubercle, hypothalamus, periaqueductal gray matter, caudate putamen, nucleus accumbens, septum, lateral thalamus, dorsal raphe nucleus and cerebellum; finally, a low labelling was apparent in the ventral tegmentum area and substantia nigra. Thus it appears that NTS2 receptors are particularly abundant in the cerebral cortex, the limbic areas and some areas involved in pain perception.

Animals↗
PubMed2001

Developmental changes of (3)H-labelled mu-opioid receptors in brainstems of intra-uterine growth-restricted rats.

The opioid mu-system is involved in brainstem-mediated respiratory control. Infants with intra-uterine growth restriction (IUGR) have more respiratory disorders in the early postnatal period. Using [(3)H]DAGO, a mu-selective ligand, and a computer-based image analysis of autoradiography, we compared the ontogeny and distribution of mu-opioid binding sites in the brainstem of IUGR and control rats in utero (E21), at birth (P0) and on postnatal days 1 (P1), P7, P10, P14 and P21. The ontogeny pattern was found to be similar in both groups. The density of the binding sites, which was low in E21, increased at P0, slightly declined at P1 and remained relatively constant thereafter. The distribution of DAGO-binding sites, also similar in both groups, was heterogeneous and was much denser in the dorsal areas of medulla and pons. In particular, binding sites were highly concentrated in nuclei involved in the cardio-respiratory function. However, DAGO-binding density was higher at all ages (except for P0 and P1) in IUGR than in control rats. Taken together, these results give at least a partial explanation for the effects of IUGR which lowers the Apgar score at birth and raises the incidence of respiratory disorders in infants.

Aging↗
PubMed2001

Pharmacokinetics of antifungal agents in onychomycoses.

Onychomycosis is caused by infection by fungi, mainly dermatophytes and nondermatophyte yeasts or moulds; it affects the fingernails and, more frequently, the toenails. Dermatophytes are responsible for about 90 to 95% of fungal infections. Trichophyton rubrum is the most common dermatophyte; Candida albicans is the major nondermatophyte yeast. Although topical therapy of onchomycosis does not lead to systemic adverse effects or interactions with concomitantly taken drugs, it does not provide high cure rates and requires complete compliance from the patient. At present there are 3 oral antifungal medications that are generally used for the short term treatment of onychomycosis: itraconazole, terbinafine and fluconazole. The persistence of these active drugs in nails allows weekly administration, reduced treatment or a pulse regimen. Good clinical and mycological efficacies are obtained with itraconazole 100 to 200 mg daily, terbinafine 250mg daily for 3 months, or fluconazole 150 mg weekly for at least 6 months. Itraconazole is a synthetic triazole with a broad spectrum of action. It is well absorbed when administered orally and can be detected in nails 1 to 2 weeks after the start of therapy. The nail : plasma ratio stabilises at around 1 by week 18 of treatment. Itraconazole is still detectable in nails 27 weeks after stopping administration. Nail concentrations are higher than the minimum inhibitory concentration (MIC) for most dermatophytes and Candida species from the first month of treatment. The elimination half-life of itraconazole from nails is long, ranging from 32 to 147 days. Terbinafine is a synthetic allylamine that is effective against dermatophytes. Terbinafine is well absorbed from the gastrointestinal tract, and the time to reach effective concentrations in nail is 1 to 2 weeks. The half-life is from 24 to 156 days, explaining the observed persistence of terbinafine in nails for longer than 252 days. Fluconazole is a bis-triazole broad spectrum antifungal with high oral bioavailability. The uptake of fluconazole by nail increases with the length of treatment, and nail : plasma ratios are generally 1.5 to 2 at steady state. Fluconazole concentrations exceed the MIC for Candida species soon after the start of treatment. Fluconazole concentrations fall slowly after the drug is stopped, with a half-life of 50 to 87 days, and fluconazole is still detectable in nails 5 months after the end of treatment. All these drugs are potent inhibitors of cytochrome P450 (CYP) enzymes and may increase the plasma concentrations of concomitantly used drugs. Itraconazole inhibits CYP3A4. Fluconazole inhibits CYP3A4, but to a lesser degree than itraconazole, CYP2C9 and CYP2C19. Terbinafine inhibits CYP2D6.

Animals↗
PubMed2000

Distal gastrectomy and Roux-Y limb in the rat: plasma motilin, pancreatic polypeptide concentrations, and duodenojejunal motility.

After gastrectomy, Roux-Y limb reconstruction leads to duodenojejunal motor disturbances. Because motilin and pancreatic polypeptide (PP) play a role in the regulation of digestive motility, their plasma concentrations were determined in rats after Roux-Y gastrectomy. Three months after a distal Roux-Y gastrectomy, coupling of electromyographic recordings and jugular samples were used to perform motilin and PP radioimmunoassays during and between activity fronts (AFs) occurring in the limb and in the duodenojejunum, 20, 40, and 60 min after intragastric instillation of a standard meal (5 ml Realmentyl). Animals that underwent a simple laparotomy, animals having isolated jejunal transection, and animals with Billroth I gastrectomy (BI group) served as control groups. After Roux-Y gastrectomy, the number of AFs in the limb (P < 0.01) and in the duodenum (P < 0.001) was reduced compared to laparotomized rats and the BI group, but did not differ from the number in the Tr group. In the limb, AFs were incompletely propagated or were retrograde in 9 and 3 of 20 animals, respectively. After Roux-Y gastrectomy, motilin concentrations occurred at the same time as each duodenal AF, and as in controls, and were independent from AFs in the limb. Plasma motilin concentrations were higher after Roux-Y reconstruction than in control groups (P < 0.03), and PP level concentrations were not different. After the meal, the interruption of AFs was shorter in Roux-Y reconstruction than in laparotomized and transected animals (P < 0.05) and than in BI group, with no significant difference in the latter. In all groups, plasma motilin and PP concentrations were decreased (P < 0.05) and increased (P < 0.001), respectively, after the meal compared to the interdigestive period. After Roux-Y gastrectomy, plasma motilin and PP levels were higher (P < 0.05) and lower (P < 0.05), respectively, compared to controls. In conclusion, AFs in the Roux-Y limb were not associated with plasma motilin concentrations, suggesting a lack of influence of motilin on the interdigestive motor status. The decrease in postprandial plasma PP concentrations may play a role in the shorter interruption of AFs after a meal.

Anastomosis, Roux-en-Y↗
PubMed2000

Operative stress response is reduced after laparoscopic compared to open cholecystectomy: the relationship with postoperative pain and ileus.

Our objective was to determine the least invasive surgical procedure; to do this we compared postoperative pain, duration of ileus, and level of neurohormonal stress response after laparoscopic cholecystectomy (LC) and open cholecystectomy (OC). Postoperative recovery of patients was faster after LC than OC but comparison of the neurohormonal stress response after laparoscopic and open surgical procedures revealed conflicting results. Forty-one consecutive patients with noncomplicated gallstones were randomized for LC (N = 25) and OC (N = 16). The stress level was evaluated in patients before surgery by the Hamilton anxiety scale. Postoperative pain was assessed by a visual analogic scale (VAS) pain score and by the amount of analgesic drugs (propacetamol) administered, while the duration of ileus was determined by the delay between surgery and the time to first passage of flatus as well by the colonic transit time (CTT) measured by radiopaque markers. Plasma concentrations of anti-diuretic hormone (ADH), adrenocorticotropic hormone (ACTH), beta-endorphin (BE), neurotensin (NT), and aldosterone (Ald) were measured before and during surgery as well as 2 and 5 hr after the surgery (D0) and on the day following surgery (D1). Urinary cortisol (uCOR) and urinary catecholamine metabolites were assessed before surgery, during D0, and on D1. Patient characteristics, the duration of surgery, and the doses of anesthetic drugs were not different in LC and OC. In LC patients the VAS pain score and the doses of postoperative antalgics were lower (P < 0.05), the time to first passage of flatus was shorter (P < 0.001), and the CTT tended to be shorter (54 +/- 12 hr vs 81 +/- 17) compared to OC patients. Patients who required the highest doses of postoperative antalgics had the longest delay to first passage of flatus (P < 0.01). During surgery, all neurohormonal parameters increased compared to the preoperative period (P < 0.05), and only plasma NT concentrations were lower during LC than OC (P < 0.05). During the postoperative period, ACTH, BE, Aid, catecholamines, and uCOR concentrations were lower in LC than in OC (P < 0.05). Concentrations of hormonal parameters were higher when the duration of surgery increased (P < 0.05). A greater need for propacetamol to relieve pain was associated with a greater increase in BE, ACTH, and urinary catecholamine levels (P < 0.05-P < 0.005). When the time to first passage of flatus was delayed, levels of BE, ACTH, and catecholamines and NT concentrations were increased (P < 0.05-P < 0.005). In conclusion, LC is less invasive because this surgical procedure induces a shorter neurohormonal stress response than OC, even if the peroperative response is not different. Postoperative pain levels and the duration of ileus are associated with BE, ACTH, and catecholamine levels and NT concentrations, suggesting the importance of hormones in postoperative functional recovery.

Adrenocorticotropic Hormone↗
PubMed1999

Are prescribed medications effective in the treatment of insomnia complaints?

Although frequently investigated in the general population, the epidemiology of insomnia complaints and their treatment have received little attention in general practice. This study recruited patients > or =15 years of age, consecutively, from 127 general practitioners in France. The physicians collected data from 11,810 of their patients, of whom 55.5% were women. Insomnia complaints were reported by 26.2% (25.4% to 27%) of the sample and use of sleep-promoting medication by 10.1% (9.7% to 10.7%). About 47% of the prescribed drugs used were anxiolytics and 45% hypnotics. Most consumers took sleep-enhancing drugs on a daily and long-term basis and most reported that the medication improved their quality of sleep. However, few distinctions emerged between elderly drug-taking insomniacs and elderly nontreated insomniacs with respect to the various dimensions of sleep. Results underscore the persistent general tendency among French general practitioners to overprescribe anxiolytics for the treatment of insomnia complaints and that they do so on a long-term basis, despite the findings of numerous studies showing that benzodiazepines are ineffective in the treatment of sleep complaints over the long term.

Adolescent↗
PubMed1999

Erythropoietin blood level is increased in sudden infant death.

Erythropoietin (EPO) is the main red cell growth factor and its release into the blood stream is stimulated by anemia and also by various kinds of hypoxia. We studied the blood EPO concentration in a population of 96 infants who died suddenly and compared their mean EPO levels to control infants. The normal values were low at birth and progressively increased during the first 2 years. In the sudden infant death (SID) group the EPO level was significantly higher (p = 0.001) for the entire population and particularly in the youngest group (0-2 months): 14.7 +/- 2.4 IU/l (mean +/- SEM) in SID group vs. 3.6 +/- 0.4 IU/l in control group (p < 0.001). Although we could not analyze the blood hemoglobin concentration after death, the anemia hypothesis was refuted by an assay of the percentage of fetal hemoglobin which was normal for age in the control and SID groups. Moreover, there was no significant difference in EPO levels between explained and unexplained deaths. We also observed an increase in the stress hormones, cortisol and beta-endorphin, in the entire SID group. These SID results suggest a profound and long-lasting hypoxia at least during terminal agony.

Adrenocorticotropic Hormone↗
PubMed1997

The melanin-concentrating hormone gene in human: flanking region analysis, fine chromosome mapping, and tissue-specific expression.

Genomic sequences encoding the human melanin-concentrating hormone (MCH) were isolated from a YAC library and subcloned in pUC vector using a novel E. coli transformation method. A 4.1-kb fragment encompassing approximately 1.0 kb of the 5'-end-flanking region, the three exons-two introns of the coding region and approximately 1.7 kb of the 3'-end-flanking region, was sequenced. Comparison with the rat MCH gene indicated strong conservation in the 5'-flanking region, in particular over the putative TATA box, CAAT box, GRE and AP-1 elements that could potentially regulate MCH gene expression. FISH with a fluorescent MCH genomic probe on human chromosomes and PCR analysis of a YAC panel mapped MCH to chromosome 12q23.1 in a region flanked by D12S1074 and D12S1030 markers. Expression of the MCH RNA species and pro-MCH-derived peptides (MCH and NEI) was investigated in human tissues by combining Northern blotting, RT-PCR, in situ hybridization, immunohistochemistry and RIA. In the human brain, MCH mRNA and MCH/NEI peptides were predominantely expressed in the lateral hypothalamus in agreement with the known distribution of MCH expression in rat. In addition, MCH gene products were detected in extra-hypothalamic sites, such as the pallidum, neocortex and cerebellum. In peripheral tissues, MCH mRNA was identified in several organs, including the thymus, brown adipose tissue, duodenum and testis. An additional shorter MCH gene transcript, likely the result of alternate splicing, was revealed in several brain areas and peripheral tissues. While only fully processed MCH and NEI were found in hypothalamus, a different peptide form, bearing MCH and NEI epitopes, was detected in peripheral organs. This represents the first evidence for differential processing of pro-MCH in mammals.

Base Sequence↗
PubMed1995

Evidence for the presence of beta 3-adrenergic receptor mRNA in the human brain.

The beta 3-adrenergic receptor (AR) is widely distributed in peripheral tissues, but up to now it has not been detected in the central nervous system. By using the polymerase chain reaction (PCR) technique, we found the beta 3-AR mRNA to be present in all the regions of the human brain we investigated. The quantities found were very low compared to those of the beta 1-AR and beta 2-AR mRNAs, being hardly detectable in adult brain. In contrast, the brain of very young infants contained about 100 times more beta 3-AR mRNA than the adult brain, whereas the amounts of beta 1-AR and beta 2-AR transcripts were essentially the same. In addition, using PCR we have cloned a central beta 3-AR coding region from a human frontal cortex cDNA library and have found it to be identical to the corresponding peripheral sequence.

Aged↗
PubMed1995

Renal hemodynamics and sodium excretion after acute and chronic administration of cicletanine in normotensive and hypertensive subjects.

We examined the effects of two therapeutic oral (p.o.) doses of cicletanine (50 and 100 mg daily) on renal hemodynamics and segmental tubular handling of sodium. Six normotensive (NT) healthy subjects (group 1) received 50 mg cicletanine, and 12 moderately hypertensive (HT) patients with normal sodium diet and randomly divided into two groups of 6 were treated either with cicletanine 50 mg (group II) or with cicletanine 100 mg (group III). Studies were performed both acutely and after 4 weeks of cicletanine administration. After 28-day treatment, blood pressure (BP) was significantly reduced in HT patients. In NT subjects (group I) and HT patients (groups II and III), acute administration of cicletanine 50 or 100 mg at day 0 did not significantly modify glomerular filtration rate (GFR) or renal blood flow (RBF), but markedly increased fractional excretion of Na (FENa) by 67% in group I and by 62 and 135% in groups II and III, respectively. Fractional distal reabsorption of Na (FDRNa) was significantly reduced in the three groups after cicletanine administration. After 4-weeks treatment, GFR and RBF were not significantly modified. The increase in FeNa and decrease in FDRNa were of the same magnitude as that at day 0. No major changes occurred in hormonal profile [renin, aldosterone, atrial natriuretic factor (ANF)]. Even at low doses, cicletanine has a natriuretic effect in NT and HT subjects. Unchanged fractional reabsorption of lithium and a significant decrease in FDRNa in the three groups suggest that this natriuretic effect occurs at the distal tubule.

Administration, Oral↗
PubMed1993

Pooling plasmas for a rapid answer in pharmacokinetic studies: application to a bioequivalence study of hydrocortisone tablets.

Two methods of plasma pooling in pharmacokinetic studies are described. The first method allows the estimation of the average plasma profile of all subjects receiving a given dose or formulation, with at most as many assays as there are time points. The second method allows to estimate the individual AUCs of all subjects with only a single assay for each drug administration. These techniques were successfully employed to predict the final results of a bioequivalence study of two formulations of hydrocortisone 10 mg tablets. Plasma pooling methods can provide early partial information on the results of pharmacokinetic studies. They can be most useful in bioequivalence studies, where early estimates of the average curves and individual AUCs can lead to a decision not to proceed with all the assays, if bioequivalence appears unlikely. The pooling methods may also have useful potential applications in Phase I ascending dose-tolerance studies and in the field of pharmacokinetic studies in small animals. Further studies are necessary to test these methods in order to gain more information on their reliability in the decision-making process in these fields as well as in bioequivalence studies.

Adult↗
PubMed1992

Ontogenesis and binding properties of high-affinity neurotensin receptors in human brain.

The ontogenesis of neurotensin binding sites was studied in human brain of subjects deceased from Sudden Infant Death Syndrome. Monoiodo-Tyr3 neurotensin specifically recognized 2 distinct classes of binding sites in human brain homogenate. The high affinity sites were already present at birth and increased to a maximal level of 240 fmol/mg protein 1 month after birth. Thereafter, the density of these sites decreased to reach a value of 8 fmol/mg protein in 15-month-old brain, a value similar to that found in adult brain. The dissociation constant of the high-affinity sites (about 0.3 nM) did not vary from birth to adulthood. The high-affinity binding sites were sensitive to GTP which decreased their affinity for neurotensin by a factor of 3, indicating that these sites are functional receptors coupled to GTP-binding proteins. By contrast, the low-affinity sites were insensitive to GTP and could be partly blocked by the antihistaminic drug levocabastine. These sites were absent in human brain during the first post-natal year and could be detected only in brain homogenate of 15-month-old infants. The transient increase in high-affinity neurotensin binding sites after birth suggests that neurotensin could act as a regulatory peptide during brain development.

Aging↗