Metoclopramide pretreatment attenuates emergency contraceptive-associated nausea

OBJECTIVE: The study was undertaken to determine whether metoclopramide pretreatment attenuates side effects associated with high-dose estrogen/progestin emergency contraception in at-risk patients. STUDY DESIGN: This was a randomized, prospective, double-blind, placebo-controlled study at the University of Kansas. Patients (141) requesting emergency contraception and lacking contraindications were offered entry in the study. Both the treatment (metoclopramide 10 mg) and placebo groups received active emergency contraception. Participants evaluated symptom severity with a 12-question survey tool developed for this study. RESULTS: Metoclopramide pretreatment provided protection against nausea and cramping associated with estrogen/progestin emergency contraception. The average scores on a 10-point scale for the treatment group and placebo group were as follows: nausea 3.2 versus 4.8 (P =.01) and cramping 0.9 versus 2.2 (P <.01), indicating less severe nausea and cramping in the treatment group. CONCLUSION: Metoclopramide pretreatment attenuates the nausea and cramping associated with Yuzpe emergency contraceptive treatment.     

Pharmacological and functional characterisation of dopamine D4 receptors in the rat retina

In the retina, activation of dopamine receptors, particularly the D2-like family (D2, D3, D4 receptor subtypes), with quinpirole suppresses the light sensitive cAMP pool and inhibits melatonin synthesis in photoreceptor cells. We have characterised rat retinal D4 receptors using the D4 selective radioligand [¹²⁵I] L-750667 which bound specifically and saturably to rat retinal membranes with high affinity (K_d 0.06±0.02 nM) and exhibited a D4 receptor pharmacology. Comparison of the binding kinetics of [¹²⁵I] L-750667 and [³H] spiperone revealed B_max values of 134±27 fmol/mg and 219±47 fmol/mg respectively, indicating that the dopamine D4 receptor is a major component of D2-like dopamine receptors in the rat retina. Modulation of retinal cAMP levels by quinpirole was used to evaluate the functional relevance of rat retinal dopamine D4 receptors. Quinpirole (0.03–3 μM) produced a dose-related decrease of the light sensitive cAMP pool which was reversed by haloperidol, clozapine and the D4 selective antagonist, L-745870 with a rank order of potency suggesting that the quinpirole effect is due to activation of the dopamine D4 receptors. The D2 selective ligand L-741626 had no effect on the quinpirole response confirming that the D4 receptor is the major receptor subtype mediating dopamine induced suppression of adenylate cyclase in the retina.     

HAEMOGLOBINURIA IN ERYTHROBLASTOSIS FETALIS

ABSTRACT. Urinary total protein excretion and the pattern of urinary proteins-one of which was haemoglobin-has been determined in 9 newborns suffering from haemolytic anaemia and hyperbilirubinaemia due to anti-D isoimmunization and in 10 healthy newborns. Eight of the 9 newborns with erythroblastosis fetalis showed elevated urinary total protein excretion and augmented haemoglobinuria. The possible toxic effect of the haemoglobinuria and hyperbilirubinaemia on the tubular functions is discussed.     

A multiple-frequency, multiple-region pattern electroretinogram investigation of non-linear retinal signals

It has been proposed that the spatial frequency doubled (FD) illusion may originate from Y-like non-linear retinal ganglion cells. If the contrast of multi-frequency stimuli is increased, Y cells show a phase advance in the self-sum frequencies but not in other output frequencies. We looked for these effects with a multi-region pattern electroretinogram (PER.G) displaying the sum of two temporal frequencies in each visual field location. Regional variation was found in the recorded sum and difference frequencies. The results indicate that PERG signals become dominated by responses from Y-like cells when the FD illusion is seen.     

Clarification of the identity of the major M2 autoantigen in primary biliary cirrhosis.

1. In primary biliary cirrhosis, the major M2 autoantigen, reacting with antimitochondrial antibodies in sera from greater than 90% of patients, has been identified as the E2 component of the pyruvate dehydrogenase complex. However, two recent reports suggest that alternative polypeptides may be major autoantigens. 2. The evidence that a 75 kDa subunit of complex I of the respiratory chain is a major autoantigen (Frostell, Mendel-Hartvig, Nelson, Totterman, Bjorkland & Ragan, Scand. J. Immunol. 1988; 28, 157-65) is refuted. The findings of Frostell et al. can be explained by contamination of complex I with the pyruvate dehydrogenase complex, evidence for which is presented here. 3. Inspection of the partial amino acid sequence of an unidentified mitochondrial autoantigen (Muno, Kominami, Ishii, Usui, Saituku, Sakakibara & Namihisa, Hepatology 1990; 11, 16-23) shows that it is the E1 beta-subunit of the pyruvate dehydrogenase complex, previously identified as a major autoantigen, and not a 'new' alternative major autoantigen. 4. These findings substantiate previous work showing that the mitochondrial M2 autoantigens identified so far in primary biliary cirrhosis are all polypeptide components of the pyruvate dehydrogenase complex or the other related 2-oxo acid dehydrogenase complexes.