The effects of acepromazine on human ether-à-go-go-related gene (hERG) potassium channels were investigated using whole-cell voltage-clamp technique in human embryonic kidney (HEK293) cells transfected with hERG. The hERG currents were recorded with or without acepromazine, and the steady-state and peak tail currents were analyzed for the evaluating the drug effects. Acepromazine inhibited the hERG currents in a concentration-dependent manner with an IC₅₀ value of 1.5 µM and Hill coefficient of 1.1. Acepromazine blocked hERG currents in a voltage-dependent manner between –40 and +10 mV. Before and after application of acepromazine, the half activation potentials of hERG currents changed to hyperpolarizing direction. Acepromazine blocked both the steady-state hERG currents by depolarizing pulse and the peak tail currents by repolarizing pulse; however, the extent of blocking by acepromazine in the repolarizing pulse was more profound than that in the depolarizing pulse, indicating that acepromazine has a high affinity for the open state of the channels, with a relatively lower affinity for the closed state of hERG channels. A fast application of acepromazine during the tail currents inhibited the open state of hERG channels in a concentration-dependent. The steady-state inactivation of hERG currents shifted to the hyperpolarized direction by acepromazine. These results suggest that acepromazine inhibits the hERG channels probably by an open- and inactivated-channel blocking mechanism. Regarding to the fact that the hERG channels are the potential target of drug-induced long QT syndrome, our results suggest that acepromazine can possibly induce a cardiac arrhythmia through the inhibition of hERG channels.
Acepromazine* ; Arrhythmias, Cardiac ; Humans* ; Kidney* ; Long QT Syndrome ; Patch-Clamp Techniques ; Potassium Channels* ; Potassium* ; Tail

The purpose of this study was to verify whether small intestinal peristalsis could be observed and quantitatively assessed using pulsed-Doppler ultrasound. Pulsed-Doppler ultrasound was used to evaluate small intestinal peristalsis after a meal in ten normal dogs and ten sedated dogs. The small intestinal peristalses were measured 0, 1, 3, 6, 9, 12, and 24 hours after a 24-hour fast and after feeding. The number of small intestinal peristalsis were 0.133/min, 0.100/min, 0.033/min, 0.167/min, 0.070/min, 0.067/min, and 0.100/min in the fasted dogs, and 1.667/ min, 0.933/min, 1.133/min, 1.234/min, 1.933/min, 1.533/ min, and 0.533/min in fed dogs, respectively. In the dogs sedated with xylazine HCl, the number of small intestinal peristalsis was significantly reduced (p<0.01). However, in the dogs treated with ketamine HCl and acepromazine, the number of small intestinal peristalsis remained unchanged. Therefore, it can be concluded that pulsed-Doppler ultrasound allows graphic visualization of the intestinal movements, which can be subjected to qualitative and quantitative analysis, and may be suitable for a non-invasive study of small intestinal motility.
Acepromazine/pharmacology ; Animals ; Dogs ; Dopamine Antagonists/pharmacology ; Excitatory Amino Acid Antagonists/pharmacology ; *Gastrointestinal Motility/drug effects ; Intestine, Small/drug effects/*physiology/ultrasonography ; Ketamine/pharmacology ; Peristalsis/drug effects/*physiology ; Ultrasonography, Doppler, Pulsed/methods/*veterinary

BACKGROUNDHilar cholangiocarcinoma is a malignant tumor that is difficult to cure. The aim of this study was to observe the effects of flow-controlled partial portal vein arterializations (PPVA) on liver regeneration after hepatectomy in minipigs with chronic obstructive jaundice.

METHODSEight minipigs were made into chronic obstructive jaundice models. United semi-hepatectomy, which imitates extended radical surgery for treatment of hilar cholangiocarcinoma, was then performed. The eight minipigs were randomly divided into groups A and B (n = 4 minipigs each). PPVA was performed in Group A but not in Group B. The effects of flow-controlled PPVA on live regeneration after hepatectomy were observed for 30 days after hepatectomy.

RESULTSThe portal vein PO(2) at the immediate time point and on postoperative day 30 was higher in Group A ((47.33 ± 2.43) and (48.50 ± 4.44) mmHg) than in Group B ((35.38 ± 4.06) and (35.55 ± 2.55) mmHg respectively, all P < 0.01). The mitotic index of liver cells on postoperative days 14 and 21 was higher in Group A (12.55% ± 2.85% and 15.25% ± 1.99% respectively) than in Group B (6.85% ± 2.10% and 11.88% ± 1.15% respectively, all P < 0.05). The regeneration rate of residual liver on postoperative days 14 and 21 was higher in Group A (24.56% ± 6.15% and 70.63% ± 9.83% respectively) than in Group B (11.96% ± 5.43% and 44.92% ± 7.42% respectively, P < 0.05 and P < 0.01 respectively).

CONCLUSIONFlow-controlled PPVA can promote liver regeneration after hepatectomy and prevent liver failure in minipigs with chronic obstructive jaundice.

Acepromazine ; therapeutic use ; Animals ; Arteriovenous Shunt, Surgical ; methods ; Atropine ; therapeutic use ; Female ; Hepatectomy ; methods ; Jaundice, Obstructive ; surgery ; Ketamine ; therapeutic use ; Liver Regeneration ; physiology ; Portal Vein ; surgery ; Swine ; Swine, Miniature

In acupuncture practice of animals, preanesthetics sometimes are needed. The purpose of this study was to select the ideal chemical restraint at acupuncture for gastric motility. Nine healthy mixed breed dogs weighed 10-21 kg and aged 1-3 years old were used in this study. Two EMG surface electrodes were placed between the seromuscular and the mucosal layer of pylorus. Twenty minutes after feeding normal gastric motility was recorded for 60 minutes using physiograph (Narco-Biosystem). Then preanesthetic treated-gastric motility was observed for 30 minutes. Preanesthetics used were xylazine, diazepam, and acepromazine. Acupuncture needles were inserted to BL-21 (Wei-Yu) acupoint, and then changes of gastric motility were recorded for 60 minutes. The gastric motility following xylazine administration (1 mg/kg, IV) was markedly decreased. BL-21 (Wei-Yu) acupoints stimulation did not alter xylazine-induced depression of gastric motility. The diazepam (1 mg/kg IV) treated-gastric motility was increased mildly 20 minutes after drug administration. BL-21 (Wei-Yu) acupoint stimulation after diazepam administration enhanced gastric motility significantly. The gastric motility following acepromazine (0.3 mg/kg, IM) administration was not changed compared with normal gastric motility. Application of traditional acupuncture at BL-21 (Wei-Yu) significantly increased the gastric motility. Based on these results, acepromazine and diazepam could be acceptable chemical restraints for acupuncture therapy of gastric motility, but xylazine couldn't be.
Acepromazine ; Acupuncture/*standards ; *Acupuncture Points ; Adjuvants, Anesthesia ; Adrenergic alpha-Agonists ; Animals ; Antipsychotic Agents ; Atropine ; Diazepam ; Dogs/*physiology ; Dopamine Antagonists ; Electromyography/veterinary ; Gastrointestinal Motility/drug effects/*physiology ; Hypnotics and Sedatives ; Metoclopramide ; Parasympatholytics ; Preanesthetic Medication/standards/*veterinary ; Xylazine