Breast feeding-induced effects on plasma gastrin and somatostatin levels and their correlation with milk yield in lactating females

Maternal gastrin and somatostatin levels have been shown to be influenced during suckling in dogs and pigs. The present study was performed to investigate whether the levels of gastrin and somatostatin are influenced by breast feeding in lactating women. Repeated blood samples were drawn in connection with nursing in 15 females and plasma levels of gastrin and somatostatin were measured by radioimmunoassay. Gastrin levels rose significantly (P = 0.01) within two minutes after onset of suckling. Somatostatin levels either decreased or increased as an effect of breast feeding. The direction of the change was correlated to the pre-suckling somatostatin levels (P less than 0.01). The somatostatin level recorded 60 min after start of breast feeding was significantly lower than basal levels (P less than 0.01) indicating a long-term inhibitory effect on somatostatin secretion. The suckling-induced effect on somatostatin levels was correlated with the amount of milk ejected (Rs - 0.52, P less than 0.05). The mechanism by which suckling influences circulating gastrin and somatostatin levels is unknown, but we suggest that suckling leads to a reflex activation of the vagal nerves, which influence the release of these hormones from the stomach. The size of the gastrointestinal tract is increased during pregnancy and lactation, illustrating that the maternal digestive capacity is adapted to the high demand for energy intake occurring during lactation. We speculate that the suckling stimulus enhances gastric functions by influencing the release of gastrin and somatostatin, which stimulate and inhibit gastric functions and growth, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

N,N-Dialkylated monophenolic trans-2-phenylcyclopropylamines: novel central 5-hydroxytryptamine receptor agonists

N,N-Dialkylated monophenolic derivatives of trans-2-phenylcyclopropylamine were synthesized and tested for central 5-hydroxytryptamine (5-HT) and dopamine (DA) receptor stimulating activity by use of a biochemical test method in rats. A hydroxy substituent in the 2- or 3-position of the phenyl ring was required for 5-HT-receptor stimulation. N,N-Diethyl or N,N-di-n-propyl substitution gave the most potent 5-HT-receptor agonists. The 4-hydroxy and 3,4-dihydroxy derivatives of trans-2-phenyl-N,N-di-n-propylcyclopropylamine were inactive at central DA and 5-HT receptors. In contrast, the corresponding 3-hydroxy derivative 18 and some of its derivatives weakly affected both DA and NE synthesis. Two of the most potent 5-HT-receptor agonists, trans-2-(2-hydroxyphenyl)-N,N-di-n-propylcyclopropylamine (8) and the 3-hydroxy isomer 18 were resolved into the enantiomers. The 1R,2S enantiomers of 8 and 18 displayed 5-HT activity, while the 1S,2R enantiomers were inactive. Compound (1R,2S)-18, but not (1R,2S)-8, weakly affected rat brain DA and NE synthesis.

Age-dependent effects of beta 2-adrenergic-stimulating drugs on fetal rabbit lung liquid and adrenal catecholamines

The effects of the beta 2-adrenergic-stimulating drug, terbutaline, were studied on fetal rabbit lung liquid (FLL) at gestational ages between 25 and 30 days. At delivery terbutaline reduced FLL in rabbit fetuses with a gestational age of 26-30 days. The most pronounced reduction of FLL was seen at 28 days. Terbutaline administration reduced the wet lung weight/body weight (WLW/BW) ratio at delivery in the 28- and 30-day-old rabbit pups. In the 26-day-old animals, beta 2-adrenergic stimulation had no significant effect on the WLW/BW ratio and at 25 days of gestational age the ratio was increased. After parturition, however, the difference in WLW/BW between the terbutaline and control animals, seen at birth, was attenuated and, at 60 min of postnatal age, the difference was no longer observed. Terbutaline decreased the adrenal content of noradrenaline and adrenaline most marked at 28 days of gestational age, but did not alter the adrenaline/noradrenaline ratio. Furthermore, adrenal dopamine was decreased after terbutaline, suggesting a decreased catecholamine synthesis. Our data show that a positive effect of terbutaline on FLL in rabbit pups was most marked during late but not early gestational age. beta 2-Adrenergic treatment may, however, reduce adrenal catecholamines.

N-substituted 1,2,3,4,4a,5,6,10b-octahydrobenzo[f]quinolines and 3-phenylpiperidines: effects on central dopamine and sigma receptors

N-Substituted analogues of trans-7- and trans-9-hydroxy-1,2,3,4,4a,5,6,10b-octahydrobenzo[f]quinoline (trans-7- and trans-9-OH-OHBQ) were tested for dopamine (DA) D2 receptor affinity by using in vitro [3H]spiperone and in vivo 5,6-di-n-Pr-ADTN binding assays. Potencies at central pre- (auto-) and postsynaptic DA receptors were determined by a biochemical and a behavioral method, respectively. Corresponding data were included for analogous, resolved 3-(3-hydroxyphenyl)piperidines and a few other substituted, racemic 3-phenylpiperidines. Beside the central dopaminergic effects of these compounds, previously reported sigma receptor affinity data [[3H]-(+)-3-(3-hydroxyphenyl)-N-n-propylpiperidine; [3H]-(+)-3-PPP] were also taken into account for a comparison of the structure-activity/affinity relationships of these compounds at these two receptor types. Larger N-substituents in both phenylpiperidines and OHBQs increase both pre- and postsynaptic dopaminergic activity. An n-propyl group gives high dopaminergic efficacy at both receptor sites (pre- and postsynaptic) in all series. However, even higher dopaminergic potency is observed for trans-7-OH-OHBQs and (S)-3-(3-hydroxyphenyl)piperidines with N-substituents larger than n-propyl. In contrast, trans-4-n-Bu-9-OH-OHBQ is inactive, and (R)-3-(3-hydroxyphenyl)-N-n-butylpiperidine is less active at central DA receptors than its corresponding n-propyl analogue. This implies interesting differences in N-substituent sensitivity for the different classes of compounds with respect to the direction of their respective N-substituents at the drug-receptor interaction. The stereochemical and steric demands for sigma receptor affinity are much less stringent. The general trend is that, up to a certain size, the more lipophilic the N-substituent, the higher the affinity for sigma receptor sites.

(+)-cis-8-Hydroxy-1-methyl-2-(di-n-propylamino)tetralin: a potent and highly stereoselective 5-hydroxytryptamine receptor agonist

C1-Methylated derivatives of the potent 5-hydroxytryptamine (5-HT) receptor agonist 8-hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT, 1) were synthesized and tested for central 5-HT and dopamine receptor activity by use of a biochemical test method in rats. cis-8-Hydroxy-1-methyl-2-(di-n-propylamino)tetralin (8) was found to be a 5-HT receptor agonist. The (+)-enantiomer of 8 had a potency equal to that of 1, whereas (-)-8 and the trans isomer (+/-)-9 were inactive.

C1- and C3-methyl-substituted derivatives of 7-hydroxy-2-(di-n-propylamino)tetralin: activities at central dopamine receptors

C1- and C3-methyl-substituted derivatives of the potent dopamine (DA) receptor agonist 7-hydroxy-2-(di-n-propylamino)tetralin (7-OH-DPAT) have been synthesized, and their conformational preferences have been studied by use of NMR spectroscopy, X-ray crystallography, and molecular mechanics (MMP2) calculations. The compounds were tested for activity at central DA receptors, by use of biochemical and behavioral tests in rats. (1S,2R)-7-Hydroxy-1-methyl-2-(di-n-propylamino)tetralin [(+)-10] was demonstrated to be sevenfold less potent than (2R)-7-OH-DPAT as a DA receptor agonist. The other new compounds were of lower potency or inactive.

Resolved cis-10-hydroxy-4-n-propyl-1,2,3,4,4a,5,6,10b- octahydrobenzo[f]quinoline : central serotonin stimulating properties

cis-10-Hydroxy-4-n-propyl-1,2,3,4,4a,5,6,10b -octahydrobenzo[f]quinoline (4) is a centrally acting serotonin (5-HT) receptor agonist of moderate potency. Due to its semirigid character and the obvious similarity between (4aR,10bS)-4 and more potent, centrally acting 5-HT receptor agonist cis-(1S,2R)-8-hydroxy-1-methyl-2-(di-n-propylamino)tetralin (2), we carried out the preparation (via resolution of 6, a precursor of 4) and the pharmacological testing of the enantiomers of 4. We were able to show that the active enantiomers of 4 and 2 coincide in terms of stereochemistry, i.e., that it is the 4aR,10bS enantiomer of 4 that is the more active one. The absolute configuration was assigned on the basis of single-crystal X-ray analysis of the precursor (+)-6 of the active enantiomer (-)-4. Conformational analysis with molecular mechanics (MM2) calculations were performed on the N-methyl analogues of compounds cis-(1S,2R)-2 (cis-(1S,2R)-3) and cis-(4aR,10bS)-4 (cis-(4aR,10bS)-7). Both ammonium and free amine forms were subjected to these calculations. The results show a preference for the N-equatorial conformation, which is corroborated by the X-ray structure of (+)-6.HCl. The relatively low potency of compound cis-(4aR,10bS)-4 might be explained by unfavorable direction of the N-lone pair (or ammonium hydrogen) bond in this compound as compared to cis-(1S,2R)-2 and trans-(4aR,10bR)-5, which can be predicted to be the more active enantiomer of compound 5.

C3-methylated 5-hydroxy-2-(dipropylamino)tetralins: conformational and steric parameters of importance for central dopamine receptor activation

C3-Methyl-substituted derivatives of the potent dopamine (DA) receptor agonist 5-hydroxy-2-(di-n-propylamino)tetralin (5-OH-DPAT) have been synthesized and their conformational preferences have been studied by use of NMR spectroscopy, X-ray crystallography, and molecular mechanics calculations (MMP2). The compounds were tested for activity at central DA receptors, by use of biochemical and behavioral tests in rats. (2R,3S)-5-Hydroxy-3-methyl-2-(di-n-propylamino)tetralin [(-)-8] was demonstrated to be a highly potent DA receptor agonist, while the other new compounds were of low potency or inactive. Results obtained confirmed the hypothesis that the tetralin inversion angle phi and the direction of the N-electron pair (N-H) tau N are conformational parameters of critical importance for DA D2 receptor activation in the 2-aminotetralin series. The high potency of (-)-8 allowed an extension of a previously defined "partial DA D2 receptor excluded volume".

Resolved cis- and trans-2-amino-5-methoxy-1-methyltetralins: central dopamine receptor agonists and antagonists

A series of 35 stereochemically well-defined C1-methyl-substituted derivatives of the potent dopamine (DA) receptor agonist 5-hydroxy-2-(di-n-propylamino)tetralin (5-OH-DPAT) have been synthesized. The compounds were tested for central DA receptor agonistic and antagonistic activity, by use of biochemical and behavioral tests in rats. In addition, the compounds were tested for in vivo interactions with 5,6-dihydroxy-2-(di-n-propylamino)tetralin (DiPr-5,6-ADTN). On the basis of pharmacological activity profiles, the active compounds have been classified into four groups: classical pre- and postsynaptic DA receptor agonists, DA receptor agonists with preferential action at presynaptic receptors, pre- and postsynaptic DA receptor antagonists, and DA receptor antagonists with preferential action at presynaptic receptors. Results obtained indicate that both 2R and 2S enantiomers of C5-oxygenated 2-aminotetralins may be able to bind to DA receptors but that only 2S antipodes are able to activate the receptors. O-Methylation of the C5-oxygenated (1S,2R)-2-amino-1-methyltetralin derivatives tends to increase their DA receptor antagonistic activity, whereas decrease of the size of the N-substituent(s) from n-propyl to ethyl or methyl appears to increase their activity at postsynaptic DA receptors.

Dopamine autoreceptor antagonists: effects on sleep-wake activity in the rat

The effects of the putative dopamine (DA) autoreceptor antagonists cis-(+)-5-methoxy-1-methyl-2-(di-n-propylamino)tetralin, (+)-UH 232, and cis-(+)-5-methoxy-1-methyl-2-(n-propylamino)tetralin, (+)-AJ 76, on sleep-wake activity, EEG, and motor activity in the rat were studied. Both drugs induced a dose-dependent increase in wakefulness (W) and a reduction in non-REM sleep (NREMS). A definite tendency to a suppression of REM sleep (REMS) could also be observed. The results of spectral analysis indicated that EEG slow wave activity, a marker of sleep intensity, was particularly sensitive to the drugs. Slight differences between the two drugs were observed: (+)-AJ 76 seemed to be more efficacious than (+)-UH 232 in stimulating motor activity. (+)-UH 232 tended to suppress slow wave activity more strongly than (+)-AJ 76. It is suggested that the increase in W following administration of (+)-AJ 76 resulted predominantly from locomotor activation, while (+)-UH 232 might also act on dopaminergic mechanisms involved in the regulation of sleep.

The putatively selective dopamine autoreceptor antagonists (+)-AJ 76 and (+)-UH 232 stimulate prolactin release in rats

The 2-aminotetralin derivatives cis-(+)-(1S,2R)-5-methoxyl-1-methyl-2-(n-propylamino)tetralin, (+)-AJ 76, and cis-(+)-(1S,2R)-5-methoxy-1-methyl-2-(di-n-propylamino)tetralin, (+)-UH 232, are novel centrally acting stimulants with a putative action as selective dopamine (DA) autoreceptor antagonists. In the present study these compounds were evaluated with respect to their effects on prolactin release in male rats. Both (+)enantiomers caused a pronounced increase in plasma prolactin levels in previously untreated animals. The effects of (+)-AJ 76 and (+)-UH 232 were virtually similar, except for a higher initial increase after the latter compound. In agreement with earlier reports, the reserpine-induced elevation of plasma levels of prolactin was strongly suppressed by the DA autoreceptor agonist B-HT 920. This effect of B-HT 920 was completely blocked by (+)-AJ 76 and by (+)-UH 232, indicating that both (+)enantiomers antagonize lactotroph DA receptors. The present findings support the notion that lactotroph DA receptors resemble DA autoreceptors rather than postsynaptic DA receptors. A possible difference between the auto-/lactotroph vs. postsynaptic DA receptors with respect to both the responsiveness to agonists and to the affinity of pure antagonists is discussed.

(+)-AJ 76 and (+)-UH 232: central stimulants acting as preferential dopamine autoreceptor antagonists

The biochemical and behavioral effects of the putative dopamine autoreceptor antagonists cis-(+)-5-methoxy-1-methyl-2-(n-propylamino)tetralin, (+)-AJ 76 and cis-(+)-5-methoxy-1-methyl-2-(di-n-propylamino)tetralin, (+)-UH 232, were evaluated in various in vivo models in rats. Both compounds produced a marked elevation in brain dopamine synthesis and turnover with only slight effects on the synthesis and turnover of serotonin (5-HT) and noradrenaline being noted. (+)-AJ 76 and (+)-UH 232 also failed to antagonize the decrease in cortical noradrenaline synthesis rate caused by the alpha 2 agonist clonidine. The apomorphine-induced decrease in dopamine synthesis rate in gamma-butyrolactone (GBL) treated animals was completely blocked by (+)-AJ 76 and (+)-UH 232 but not by d-amphetamine or methylphenidate. In activity experiments using habituated animals, (+)-AJ 76 and (+)-UH 232 produced locomotor stimulation and weak stereotypies and antagonized the sedative effects of low doses of apomorphine. Locomotor hyperactivity induced by apomorphine or the dopamine agonist DiPr-5,6-ADTN was antagonized by (+)-UH 232 and to a lesser degree by (+)-AJ 76. The locomotor hyperactivity produced by (+)-AJ 76, (+)-UH 232 and methylphenidate was completely prevented by reserpine pretreatment and partially blocked by the tyrosine hydroxylase inhibitor alpha-methyl-para-tyrosine (alpha-MT), whereas d-amphetamine-induced hyperactivity was only antagonized by alpha-MT pretreatment. It is concluded that (+)-AJ 76 and (+)-UH 232 produce behavioral stimulation via a preferential antagonism on central dopamine autoreceptors, an action different from that of all known stimulants including apomorphine, d-amphetamine and methylphenidate. (+)-AJ 76 and (+)-UH 232 possess but weak antagonistic effects on postsynaptic dopamine receptors and only the latter compound is able to induce sedation in rats.

Enantiomers of 3-(3,4-dihydroxyphenyl)- and 3-(3-hydroxyphenyl)-N-n-propylpiperidine: central pre- and postsynaptic dopaminergic effects and pharmacokinetics

This study emphasizes the importance of the metabolic conversion of the enantiomers of 3-(3-hydroxyphenyl)-N-n-propylpiperidine (3-PPP) into their catechol analogues, the enantiomers of 3-(3,4-dihydroxyphenyl)-N-n-propylpiperidine. These isomers are both shown to be excellent substrates for COMT, with a slight preference for the S-(-) enantiomer. Assessment of the dopaminergic activity of these catechols and the results from the determination of brain levels of the enantiomers of 3-PPP and their metabolites indicate that the metabolites probably do not alter the pharmacological profiles established for (R)-(+)- and (S)-(-)-3-PPP. The conversion of the monophenols into catecholic metabolites is only 1-5%, and the further conversion of these catecholic metabolites into methoxylated analogues is very rapid. However, the very interesting observation was made that, when inhibiting COMT by means of tropolone and subsequently treating the rats with high doses of (S)-(-)-3-PPP (ip), postsynaptic dopaminergic activity was elicited. This has never been seen for (S)-(-)-3-PPP without tropolone pretreatment and might indicate that, in this special case, the catecholic metabolite affects the in vivo pharmacological profile of (S)-(-)-3-PPP.

Effects of capsaicin on central monoaminergic mechanisms in the rat

The acute and chronic effects of capsaicin (s.c.) on the monoamines in the preoptic region + hypothalamus (RPO-H), spinal cord, substantia nigra and striatum were studied. Levels of DOPA, DA, DOPAC, HVA, 3-MT, NA, Trp, 5-HTP, 5-HT and 5-HIAA were determined by means of liquid chromatography (HPLC-EC). In response to acute capsaicin treatment, the levels of DA, DOPAC and DA synthesis rate (DOPA formation) were increased in a dose-dependent manner in the RPO-H and spinal cord. The disappearance rate of NA was accelerated in both regions. In substantia nigra, increased DOPAC levels were found whereas the levels of 3-MT were decreased in striatum after acute capsaicin treatment. Only minor changes on the levels of 5-HT and 5-HIAA in the regions studied were noted. Neonatal or adult capsaicin treatment failed to affect the levels of NA, DA and 5-HT (measured two months or five weeks after injection, respectively) in the regions studied. A capsaicin injection to rats pretreated with the drug as adults did not affect either the monoamines in the RPO-H and spinal cord or the body temperature. In contrast, in rats pretreated with capsaicin as neonates, a second injection of the drug to adult animals elicited hypothermia and changes in monoamines similar to those observed in naive animals.

Central dopaminergic properties of HW-165 and its enantiomers; trans-octahydrobenzo(f)quinoline congeners of 3-PPP

In the further development of CNS dopamine autoreceptor active compounds related to 3-PPP, the transfused 7-hydroxy-1,2,3,4,4a,5,6,10b-octahydrobenzo(f)quinoline HW-165 and its enantiomers were synthesised. This paper describes the basic pharmacological properties of these latter, novel "atypical" dopaminergic agents, based on an extensive series of biochemical and behavioural experiments in rats. By and large, the pharmacological activities of HW-165 - essentially, if not exclusively, residing in its (4aS,10bS)-(-)-enantiomer - were similar to those displayed by (S)-(-)-3-PPP, indicating the simultaneous presence of central dopamine (autoreceptor) agonist and weak (postsynaptic) antagonist properties in the molecule. Thus, in non-pretreated animals HW-165 and its active species monotonically suppressed the spontaneous locomotion without causing catalepsy or other appreciable motor disabilities, and at the same time selectively reduced the dopamine synthesis, release/turnover and utilisation. Some differences in these biochemical responses to HW-165 [racemate or (-)-enantiomer] were, however, noted in the limbic vs. striatal brain areas (e.g. decrease of dopamine synthesis particularly in the limbic parts). On the other hand, while failing to reverse reserpine-induced akinesia or to elicit stereotyped behaviour, the agents markedly inhibited the dopamine synthesis in either of the dopamine-dominated cerebral regions in the reserpinised as well as in gamma-butyrolactone (GBL)-treated rats. As shown for racemic HW-165 after reserpine pretreatment, the inhibition of dopamine synthesis was completely and stereoselectively blocked by (+)-butaclamol, thereby supporting direct dopamine receptor interaction. Racemic HW-165 readily antagonised the d-amphetamine-induced locomotor hyperactivity. Apomorphine-induced hyperactivity was, however, distinctly more resistant to antagonism by HW-165 [racemate or (-)-enantiomer]. Moreover, the latter agents fully prevented the apomorphine-induced inhibition of striatal dopamine synthesis in otherwise non-pretreated rats, while only partly counteracting this effect of apomorphine in the limbic regions of such animals, and in either brain area of rats treated with gamma-butyro-lactone. The findings are interpreted within the context of the mixed dopamine agonist/antagonist properties (referred above) of HW-165 and its active (-)-species in relation to the adaptive state of central dopamine receptors and possible regional variations in feedback strength and organisation.(ABSTRACT TRUNCATED AT 400 WORDS)

Longitudinal growth of the distal fibula in children with slipped capital femoral epiphysis

The longitudinal growth rates of the distal fibula were measured, using a roentgen stereophotogrammetric method, in 32 children treated for slipped capital femoral epiphysis and compared with growth rates in a series of normal children. The growth rates in patients were similar to the growth rates in normal children, in both boys and girls. However, at the time of slippage, 13 patients had a body height exceeding the normal value by greater than 1 SD, indicating an above-average growth rate before slippage. This pattern was found in one boy whose distal fibular growth rates were measured both before and after slippage. In conclusion, there are indications that the skeletal growth rate is slightly accelerated before slippage and more normal after slippage.

A homologous series of N-alkylated cis-(+)-(1 S, 2 R)-5-methoxy-1-methyl-2-aminotetralins: central dopamine receptor antagonists showing profiles ranging from classical antagonism to selectivity for autoreceptors

N-alkylated and N,N-dialkylated cis-(+)-(1 S, 2 R)-5-methoxy-1-methyl-2-aminotetralins were tested for central dopamine receptor antagonism using in vivo biochemical and behavioral models in rats. The di-methyl analogue showed a profile similar to classical dopamine receptor antagonists. It produced a marked hypomotility including catalepsy and a pronounced increase in dopamine synthesis rate. This compound also displaced DiPr-5, 6-ADTN from striatal binding sites and antagonized the hyperactivity induced by the ligand. In contrast, the mono-propyl analogue increased locomotor activity and dopamine synthesis rate over a wide dose range. This compound failed to antagonize the hyperactivity induced by DiPr-5, 6-ADTN and to displace this in-vivo binding ligand. Thus, the mono-propyl analogue appears to lack postsynaptic dopamine receptor antagonistic properties; it seems to produce its effects via a selective dopamine autoreceptor antagonism. The di-ethyl and di-propyl, but not the dibutyl, analogues were also active in the models used. Whereas the di-ethyl compound shows a profile similar to classical dopamine receptor blockers, the di-propyl compound appears to act preferentially on autoreceptors.

(+)-UH 232 and (+)-UH 242: novel stereoselective dopamine receptor antagonists with preferential action on autoreceptors

The (+)- and (-)-enantiomers of the 2-aminotetralin derivatives cis-5-methoxy-1-methyl-2-(di-n-propylamino)tetralin (UH 232) and cis-5-hydroxy-1-methyl-2-(di-n-propylamino)tetralin (UH 242), were pharmacologically evaluated in rats in an extensive series of in vivo biochemical and behavioral experiments. These studies showed that the (+)- and (-)-enantiomers have differential effects on central dopamine (DA) receptors. Thus, (-)-UH 242 is a DA-receptor agonist stimulating both pre- and postsynaptic receptors. (-)-UH 232 is also active as a DA receptor agonist, although with much lower potency than (-)-UH 242. In contrast, (+)-UH 242 and (+)-UH 232 are characterized as DA receptor antagonists. Both (+) forms markedly accelerated DA synthesis and turnover and reversed the biochemical and behavioral effects of apomorphine. Locomotor activity was stimulated by the (+)-enantiomers over a wide dose range; hypomotility was induced only by high doses. The pharmacological profile of the (+)-enantiomers clearly differs from that of classical neuroleptics and suggests a preferential antagonistic action on DA autoreceptors. (+)-UH 232 and (+)-UH 242 may prove useful as experimental tools and as potential therapeutic agents (selectively increasing DA-ergic neurotransmission), e.g. in geriatric practice.

Design, findings and five-year follow-up of preventive medical lipid intervention clinic in Malmö

In a separate lipid intervention clinic integrated within the framework of a multiphasic preventive medical population program in Malmö, 401 of 2431 screening attenders in a male birth-year cohort born in 1927 and 1928 had elevated values of triglyceride and/or cholesterol. Hypertriglyceridemia was more than three times as frequent as hypercholesterolemia. Of these attenders 20% had normal values at the second control, 5% did not attend the second test and 92 (31.2%) of the remaining were referred to other clinics because of other high risk factors. Thus, 209 (8.6% of the screening attenders) males born in 1927 and 1928 attended the lipid clinic for isolated hyperlipidemia. Disregarding a 5-year drop-out frequency of 13 sections, a significant reduction in the lipids was obtained during the follow-up period in those remaining in treatment. This study demonstrates the feasibility in taking care of hyperlipidemic individuals after a screening detection program. Detection and treatment of hyperlipidemia should of course also be initiated in the individual case in ordinary medical practice.

Sub-chronic administration of (-)-3-PPP and central dopamine receptor sensitivity changes

The effects of sub-chronic treatment with (-)-3-PPP (8 mg/kg, s.c., b.i.d. for 21 days), a dopaminergic agent with mixed agonist/antagonist properties, were investigated by means of behavioural and in vivo biochemical methods. There was no change in basal locomotor activity and central dopamine (DA) synthesis after 24 hours withdrawal. A slight, though significant reduction of the locomotor suppressive effect and of the DA synthesis-stimulating effect of acute (-)-3-PPP challenge doses of 0.125 and 1.0 mg/kg (s.c.), respectively, were demonstrated in (-)-3-PPP-pretreated as compared to vehicle-pretreated rats. No change in either action was evident after acute challenge with 8.0 mg/kg (s.c.) of the drug. The plasma levels of (-)-3-PPP were virtually unchanged by pretreatment with active drug. The findings are discussed in terms of a modest down- and up-regulation of DA autoreceptors and postsynaptic receptors, respectively, induced by the subchronic (-)-3-PPP treatment.

Novel dopamine receptor agonists and antagonists with preferential action on autoreceptors

The enantiomers of cis-5-hydroxy-1-methyl-2-(di-n-propylamino)tetralin and its methyl ether have been synthesized. The compounds were tested for central dopamine (DA) receptor activity, by using biochemical and behavioral tests in rats. The (1R,2S)-(-) enantiomers of 1 and 2 are characterized as centrally acting DA-receptor agonists while the corresponding (1S,2R)-(+) enantiomers are characterized as centrally acting DA-receptor antagonists. Compounds (+)-1 and (+)-2 differ from classical neuroleptics in being able to increase DA synthesis rate in a wide dose range without reducing locomotor activity, suggesting a pronounced selectivity for DA autoreceptors. Also the (-) enantiomers seem to act preferentially on DA autoreceptors.

The putative dopamine autoreceptor agonist B-HT 920 decreases nigral dopamine cell firing rate and prolactin release in rat

Recent behavioural and biochemical investigations have suggested that the alpha-2 receptor agonist B-HT 920 is also a centrally acting dopamine (DA) agonist with a selectivity for autoreceptors. It is presently demonstrated that B-HT 920, in contrast to the structurally related alpha-2 agonist B-HT 933, effectively reduces the firing rate of nigral DA neurons both after intravenous and microiontophoretic administration. Furthermore, B-HT 920, but not B-HT 933, decreases plasma levels of prolactin in reserpine pretreated rats. The electrophysiological as well as the neuroendocrine effects of the drug were antagonised by DA antagonists but not by alpha-2 receptor antagonists. The data support the contention that B-HT 920 acts as an agonist at central DA autoreceptors. Furthermore, they reinforce the hypothesis that lactotroph DA receptors are more similar to DA autoreceptors than to postsynaptic DA receptors in the brain.

Prediction of long-term outcome of tibial osteotomy in medial gonarthrosis

To predict the long-term outcome after tibial osteotomy for medial gonarthrosis, multivariate statistical techniques were used and prognostic equations were defined. A comparison between different evaluation systems was also performed. Clinical and radiographic data from 81 patients followed up for more than 7 years were used. Twenty-eight preoperative variables were analysed in relation to the outcome at 7 years with the multivariate procedures discriminant analysis and cluster analysis. Among the variables, knee flexion and walking capacity were found to be the most dominant factors. Excluding the undercorrected osteotomies, preoperative walking capacity was now the dominating variable for prediction. Seven years postoperatively only small differences were found between the evaluation criteria of pain relief, London Hospital score, and HSS score. The discriminant functions for the highest ranked evaluation criteria are given in the text, as are dendrograms showing the patterns of interdependence between the evaluation criteria. Thus it was possible to transform clinical entities into factors suitable for determination and calculation of postoperative evaluation. The most commonly used evaluation systems had very similar discriminant functions showing good agreement.