Massive Pontine Hemorrhage by Dual Injection of Autologous Blood

Summary

We present a protocol to establish a massive pontine hemorrhage model in a rat via dual injection of autologous blood.

Abstract

We provide a protocol to establish a massive pontine hemorrhage model in a rat. Rats weighing about 250 grams were used in this study. One hundred microliters of autologous blood was taken from the tail vein and stereotaxically injected into the pons. The injection process was divided into 2 steps: First, 10 µL of blood was injected into a specific location, anteroposterior position (AP) -9.0 mm; lateral (Lat) 0 mm; vertical (Vert) -9.2 mm, followed by a second injection of the residual blood located at AP -9.0 mm; Lat 0 mm; Vert -9.0 mm with a 20-minute interval. The balance beam test, limb placement test, and the modified Voestch neuroscore were used to evaluate neurological function. Magnetic Resonance Imaging (MRI) was used to assess the volume of hemorrhage in vivo. The symptoms of this model were in line with patients with massive pontine hemorrhage.

Introduction

Intracerebral hemorrhage accounts for one-fifth of stroke patients. The prognosis of intracerebral hemorrhage depends on the speed, volume, and location of bleeding^1,2. Compared to the forebrain hemorrhage, the brainstem hemorrhage has higher mortality and morbidity³. About 40% of brainstem hemorrhage occurs in the pons⁴. The etiology and pathophysiology of pontine hemorrhage are quite different and less studied than forebrain hemorrhage⁵.

There are two kinds of pontine hemorrhage animal models. One is spontaneo....

Protocol

The protocol was reviewed and approved by the Institutional Animal Care and Use Committee of the Second Affiliated Hospital of Guangzhou Medical University. Rats were provided by the Animal Center of Southern Medical University. The experimental design is shown in Figure 1.

1. Animal and instruments

1. Use 8-week-old male Sprague-Dawley rats weighing 250 ± 10 g.
2. House the rats for at least 7 days before surgery under controlled environmental conditions with an ambient temperature of 25 °C, relative humidity of 65%, and a 12/12-h light-dark cycle.
3. Provide food and water wit....

Results

A total of 25 animals were used, 3 for control, 6 for 30 µL, 6 for 60 µL, and 10 for 100 µL blood injections. One rat that received a 100 µL injection of autologous blood (1/10) died within 24 hours after surgery.

Behavioral tests were conducted on Day 1, Day 3, Day 7 and Day 14 after surgery. The scores for the control group and blood-injection groups on different timepoints after surgery are presented in

Discussion

In the present study, we provided a protocol to generate a massive pontine hemorrhage rat model. This model can be used for the research on the pathophysiological mechanism and prognosis of massive pontine hemorrhage.

Throughout the experiment, 25 rats were used, of which only one died. The verification of MRI, gross anatomy, and the HE staining indicated that this method had a very low mortality rate and a high success rate. To establish massive pontine hemorrhage model, two problems must be .......

Materials

Name	Company	Catalog Number	Comments
100ml Saline solution	Guangdong yixiang	191222201 C1	Preparing heparin diluent
100μl Microinjector	Shanghai Gaoge		Injection of autologous blood
1ml Syringe	Jiangsu Zhiyu	20191014	Withdraw autologous blood from the tail vein
75% Alcohol	Shandong Lierkang		Disinfection of rat tail
Adhesive tape	Shanghai Jinzhong		Surgicl instruments
Animal anesthesia system	RWD	R510-31S-6	Inducing and maintaining anesthesia
Balance beam	Jiangsu Saiangsi		For neurological deficit scores
Blades	Shanghai Feiying	74-C	For gross anatomy
Bone cement	Shanghai Xinshiji	20180306	Surgicl instruments
Brain tank	Shenzhen LEIYEA		For gross anatomy
Butorphanol tartrate	Jiangsu Hengrui		For pain management
Electric cranial drill	Nanjing  Darwin biotechnology	20180090018	Making a burr hole on the skull
EP tube	Nantong Surui		Transfer autologous blood
Erythromycin eye cream	Yunnan pharmacy		Eyes protection
HE dye liquor	Solarbio	G1120	For HE staining
Heating pad	Dangerous Jungle	JR01	Keeping warm
Heparin sodium injection	Chengdu Haitong Pharmacal Company	190701	Preparing heparin diluent
IndoPhors	Guoyao of China		Sterilization
Isoflurane	RWD	20080701	Inducing and maintaining anesthesia
Light dark box	Jiangsu Saiangsi		For neurological deficit scores
Micro-injection pump	Baoding Leifu	TFD03-01-C	Injection of autologous blood
MRI system	Philips		Confirmation of infarction in vivo
Needle holder	Shanghai Jinzhong	J32020	Surgicl instruments
Penicilin	Guoyao of China		Infection Prevention
Q-tips	Jiangxi Songhe		Surgicl instruments
Scalp heedle	Jiangxi Hongda	20200313	Withdraw autologous blood from the tail vein
Scalpel	Shanghai Kaiyuan	170902	Surgicl instruments
Shearing scissors	Shanghai Jinzhong	Y00040	Surgicl instruments
Stereotaxic apparatus	RWD	900-00001-00	for surgical positioning
Surgical towel	Xinxiang Huakangweicai	20070601	Surgicl instruments
Suture needle	Shanghai Jinzhong		Surgicl instruments
Suture scissors	Shanghai Jinzhong	J25041	Surgicl instruments
Tissue holding forcepts	Shanghai Jinzhong	J31080	Surgicl instruments