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Synaptic circuits in the brain are precisely organized, but the processes that govern this precision are poorly understood. Here, we explore how distinct embryonic neural progenitor pools in the lateral ganglionic eminence contribute to neuronal diversity and synaptic circuit connectivity in the mouse striatum. In utero labeling of Tα1-expressing apical intermediate progenitors (aIP), as well as other progenitors (OP), reveals that both progenitors generate direct and indirect pathway spiny projection neurons (SPNs) with similar electrophysiological and anatomical properties and are intermingled in medial striatum. Subsequent optogenetic circuit-mapping experiments demonstrate that progenitor origin significantly impacts long-range excitatory input strength, with medial prefrontal cortex preferentially driving aIP-derived SPNs and visual cortex preferentially driving OP-derived SPNs. In contrast, the strength of local inhibitory inputs among SPNs is controlled by birthdate rather than progenitor origin. Combined, these results demonstrate distinct roles for embryonic progenitor origin in shaping neuronal and circuit properties of the postnatal striatum., Competing Interests: Declaration of interests The authors declare no conflict of interest., (Copyright © 2021 The Author(s). Published by Elsevier Inc. All rights reserved.)

Key Points: Imbalances in the activity of the D1-expressing direct pathway and D2-expressing indirect pathway striatal projection neurons (SPNs) are thought to contribute to many basal ganglia disorders, including early-onset neurodevelopmental disorders such as obsessive-compulsive disorder, attention deficit hyperactivity disorder and Tourette's syndrome. This study provides the first detailed quantitative investigation of development of D1 and D2 SPNs, including their cellular properties and connectivity within neural circuits, during the first postnatal weeks. This period is highly dynamic with many properties changing, but it is possible to make three main observations: many aspects of D1 and D2 SPNs progressively mature in parallel; there are notable exceptions when they diverge; and many of the defining properties of mature striatal SPNs and circuits are already established by the first and second postnatal weeks, suggesting guidance through intrinsic developmental programmes. These findings provide an experimental framework for future studies of striatal development in both health and disease., Abstract: Many basal ganglia neurodevelopmental disorders are thought to result from imbalances in the activity of the D1-expressing direct pathway and D2-expressing indirect pathway striatal projection neurons (SPNs). Insight into these disorders is reliant on our understanding of normal D1 and D2 SPN development. Here we provide the first detailed study and quantification of the striatal cellular and circuit changes occurring for both D1 and D2 SPNs in the first postnatal weeks using in vitro whole-cell patch-clamp electrophysiology. Characterization of their intrinsic electrophysiological and morphological properties, the excitatory long-range inputs coming from cortex and thalamus, as well their local gap junction and inhibitory synaptic connections reveals this period to be highly dynamic with numerous properties changing. However it is possible to make three main observations. Firstly, many aspects of SPNs mature in parallel, including intrinsic membrane properties, increases in dendritic arbours and spine densities, general synaptic inputs and expression of specific glutamate receptors. Secondly, there are notable exceptions, including a transient stronger thalamic innervation of D2 SPNs and stronger cortical NMDA receptor-mediated inputs to D1 SPNs, both in the second postnatal week. Thirdly, many of the defining properties of mature D1 and D2 SPNs and striatal circuits are already established by the first and second postnatal weeks, including different electrophysiological properties as well as biased local inhibitory connections between SPNs, suggesting this is guided through intrinsic developmental programmes. Together these findings provide an experimental framework for future studies of D1 and D2 SPN development in health and disease., (© 2019 The Authors. The Journal of Physiology published by John Wiley & Sons Ltd on behalf of The Physiological Society.)

Aims: A double-blind randomised study was performed to compare the dose-effect and dose-tolerability relationships between the alpha-glucosidase inhibitor miglitol in doses of 25 mg, 50 mg, 100 mg and 200 mg all t.i.d. vs placebo t.i.d. in patients with Type 2 diabetes mellitus on diet only., Methods: After a 6-week placebo run-in period 468 patients with a fasting blood glucose > or = 7 mmol/l as well as a HbA1c between 6.1% and 10.4% were randomised for a 24-week treatment period., Results: The results of 465 patients were valid for safety analysis and of 384 patients for the efficacy analysis. In the placebo group the HbA1c level increased by 0.40+/-1.46% as compared with baseline. The decrease in the mean HbA1c values (corrected for differences in baseline values) was significant and dose-dependent for all miglitol groups compared with placebo, being -0.46% (95% CI: -0.91%, -0.01%) in the 25 mg group, -0.45% (95% CI: -0.90%, -0.003%) in the 50 mg group, -0.84% (95% CI: -1.31%, -0.37%) in the 100 mg group and -1.26% (95% CI: -1.76%, -0.76%) in the 200 mg group. Blood glucose levels following a standardised breakfast tolerance test were significantly and dose-dependently lower for all the miglitol doses at 12 and 24 wk of treatment compared to baseline: in comparison with baseline maximum blood glucose increased by 4% with placebo and decreased by 7%, 14%, 24% and 33% with miglitol 25 mg, 50 mg, 100 mg and 200 mg t.i.d. respectively. The same pattern was seen with postprandial maximal serum insulin levels which decreased by 8% under placebo and by 17%, 26%, 25% and 35% with the 25 mg to 200 mg doses of miglitol. The adverse events reported were mainly of gastrointestinal nature, mostly being flatulence, diarrhoea and abdominal pain and the incidence increased with increasing dose. Although the side effects were not serious, they were troublesome, leading to a considerable drop-out rate increasing with dose., Conclusions: The alpha-glucosidase inhibitor miglitol in Type 2 diabetic patients on diet alone decreases both HbA1c levels and postprandial glucose and insulin levels in a dose-dependent manner. Gastrointestinal side effects also showed dose-dependency. Combination of efficacy and safety results leads to the conclusion that the optimal dose of miglitol will be in the range of 50 to 100 mg t.i.d.

Host kidneys may contribute considerably to hypertension after renal transplantation. Their role in sustaining hypertension is more prominent if glomerulonephritis (GN) than if interstitial nephritis (IN) is the original renal disease. We compared the antihypertensive effect of beta-blockade in IN (n = 10) and GN (n = 19) hypertensive renal transplant recipients with host kidneys in situ with those who had undergone bilateral nephrectomy (BN, n = 10). Pretreatment blood pressures were comparable in BN, IN, and GN patients, being 165 +/- 6/108 +/- 3, 172 +/- 5/104 +/- 3, and 161 +/- 3/104 +/- 1, mmHg, respectively. Blood pressure did not change on beta-blockade in BN patients, whereas it decreased significantly more (P less than 0.001) in GN than in IN patients, changes of mean arterial pressure being -107 +/- 1.0, -14.9 +/- 1.3, and -6.8 +/- 1.6%, respectively. This failure to respond to beta-blockade in patients without host kidneys may be related to low activity of the renin-angiotensin system or to functional denervation of the grafted kidney. Further investigations of this phenomenon may clarify the mechanism of antihypertensive action of beta-blockade as well as the nature of hypertension after renal transplantation.