This model was developed with the financial support from Ministry of Science and Technology, Taiwan (MOST 109-2320-B-030-006-MY3). This manuscript was edited by Wallace Academic Editing.

All animal experiments were conducted in accordance with the Guide for the Care and Use of Laboratory Animals, published by the US National Institutes of Health (NIH publication no. 85-23, revised 1996). The study protocol was approved by and in accordance with the guidelines of the Institutional Animal Care and Use Committee at Fu-Jen Catholic University. See the Table of Materials for details about all materials and instruments used in this protocol.
1. Prepar...

The authors declare that there is no conflict of interest regarding the publication of this article.

The proposed bilateral IR-AKI protocol is suitable for investigating the mechanism of hypoperfusion and reperfusion injury of both kidneys. The protocol suggests that lightweight mice, general anesthesia with isoflurane, a dorsolateral approach to the surgery, and body temperature maintenance during the operation mitigate the associated technical difficulties, shorten the duration of the surgery, and increase the consistency of the procedure for acute bilateral renal IR-AKI research.
Technical...

Cardiac arrest occurs more than 80,000 times annually in the United States1,2. The mortality rate of cardiac arrest is extremely high3,4,5,6. AKI is a major risk factor associated with high mortality and poor neurological outcomes in patients with cardiac arrest after ROSC7,8,9,10,11,12,13. Recovery from AKI is a good predictor of favorable neurological outcomes and discharge from the hospital14,15,16. However, effective therapies for IR-AKI are still lacking15,16,17,18,19. Additional therapeutic strategies are required to further improve the clinical outcomes of the disease.
IR-AKI with bilateral renal ischemia approach is one of the animal models used for AKI research20,21,22,23,24,25,26. Renal IR-AKI animal models are less complicated than a whole-body IR injury model for the study of AKI in patients with sudden cardiac arrest following ROSC6,27,28,29,30. This implies that consistent results from a renal IR-AKI animal model are easier to achieve because of the presence of fewer confounding factors in experiments. Moreover, renal IR-AKI protocols commonly involve a unilateral or bilateral renal pedicle occlusion. Conditions in experiments on bilateral renal IR-AKI are comparable to clinical conditions for AKI following ROSC in patients with sudden cardiac arrest after successful cardiopulmonary resuscitation. Although the pathological characteristics of the kidneys in both models reflect the pathological characteristics of human renal IR injury31,32,33, a bilateral renal ischemia approach is more relevant to AKI under human pathological conditions, such as cardiac failure, vasoconstriction, and septic shock35. Bilateral renal IR-AKI animal models are suitable for studies focusing on renal IR injuries in cardiac arrest following ROSC.
Bilateral renal IR-AKI models are associated with technical difficulties, experimental complexity, and long surgery duration23,26,32,33,35,36. To overcome these technical difficulties, the present study established a reliable bilateral IR-AKI research protocol in mice by making some technical modifications. The proposed protocol resulted in fewer surgical complications, less tissue damage, and a lower likelihood of mortality during surgery. Therefore, it can be used to investigate the pathophysiological processes of AKI after ROSC to develop new therapeutic strategies against renal hypoperfusion and reperfusion damage37,38,39.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>Absorbable Suture, 6-0</td>
			<td>Ethicon</td>
			<td>J510G-BX</td>
			<td></td>
		</tr>
		<tr>
			<td>Betadine solution</td>
			<td>Shineteh Istrument</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Carprofen</td>
			<td>Sigma</td>
			<td>PHR1452</td>
			<td></td>
		</tr>
		<tr>
			<td>Cotton balls</td>
			<td>Shineteh Istrument</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Graefe Forceps</td>
			<td>Fine Science Tools</td>
			<td>11051-10</td>
			<td></td>
		</tr>
		<tr>
			<td>Heating pad</td>
			<td>Shineteh Istrument</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Isoflurane</td>
			<td>Piramal Critical Care Inc.</td>
			<td>26675-46-7</td>
			<td></td>
		</tr>
		<tr>
			<td>Moria Vessel Clamp</td>
			<td>Fine Science Tools</td>
			<td>18320-11</td>
			<td></td>
		</tr>
		<tr>
			<td>Olsen-Hegar needle holder</td>
			<td>Fine Science Tools</td>
			<td>12002 - 12</td>
			<td></td>
		</tr>
		<tr>
			<td>Saline</td>
			<td>Shineteh Istrument</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Scalpel blades</td>
			<td>Shinva</td>
			<td>s2646</td>
			<td></td>
		</tr>
		<tr>
			<td>Small Animal Anesthesia Machine</td>
			<td>Sheng-Cing Instruments Co.</td>
			<td>STEP AS-01</td>
			<td></td>
		</tr>
		<tr>
			<td>Tissue scissors</td>
			<td>Fine Science Tools</td>
			<td>14072 - 10</td>
			<td></td>
		</tr>
	</tbody>
</table>

technical refinement of a bilateral renal ischemia-reperfusion mouse model for acute kidney injury research

Cardiac arrest poses a large public health burden. Acute kidney injury (AKI) is an adverse marker in survivors of cardiac arrest following the return of spontaneous circulation (ROSC) after successful cardiopulmonary resuscitation. Conversely, recovery of kidney function from AKI is a predictor of favorable neurological outcomes and hospital discharge. However, an effective intervention to prevent kidney damage caused by cardiac arrest after ROSC is lacking, suggesting that additional therapeutic strategies are required. Renal hypoperfusion and reperfusion are two pathophysiological mechanisms that cause AKI after cardiac arrest. Animal models of ischemia-reperfusion-induced AKI (IR-AKI) of both kidneys are comparable with patients with AKI following ROSC in a clinical setting. However, IR-AKI of both kidneys is technically challenging to analyze because the model is associated with high mortality and wide variation in kidney damage, which may affect the analysis. Lightweight mice were chosen, placed under general anesthesia with isoflurane, subjected to surgery with a dorsolateral approach, and their body temperature maintained during operation, thereby reducing tissue damage and establishing a reproducible acute renal IR-AKI research protocol.

The quality of the bilateral renal IR-AKI surgery should be assessed before further microscopic or molecular analysis. During surgery, renal ischemia should be confirmed by seeing whether the kidney has changed color from pink to dark red soon after the renal pedicle is clamped with a microvascular clip (Figure 1). After surgery, kidney damage caused by IR-AKI surgery can be further validated with a few microliters of serum through submandibular blood collection for biochemical analysis wher...

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Technical Refinement of a Bilateral Renal Ischemia-Reperfusion Mouse Model for Acute Kidney Injury Research

This study established a protocol focusing on the technical refinement of a mouse model of bilateral renal ischemia-reperfusion for acute kidney injury research.

Cardiac arrest poses a large public health burden. Acute kidney injury (AKI) is an adverse marker in survivors of cardiac arrest following the return of ...

Acute kidney injury is a major risk factor associated with high mortality in patients with cardiac arrest after return of circulation. This procedure can be performed to induce acute kidney injury. This protocol is to induce renal ischemia reperfusion accurately, securely, and consistently.Demonstrating the procedure will be Huang Cheng-Wei, an assistant from my laboratory. To begin, place an anesthetized eight-week-old C57BL/6 male mouse in the prone position on a surgery platform with an electric blanket to maintain body temperature. Next, touch the back, find the lumbar spine, and look for costovertebral angles below both sides of the last rib.Apply hair removal lotion to shave and scrub the hair near both sides of the costovertebral angle region. Disinfect the surgical area using a Betadine solution and 75%alcohol using cotton balls. Use fine tip forceps to gently lift the skin below the left costovertebral angle.Then, using scissors, create a one-centimeter oblique dorsolateral incision along the skin tension lines from the lumbar midline on the left flank. Next, transect the muscle wall of the left flank to visualize the left kidney. Push and separate the left kidney carefully from the surrounding tissue with forceps.Then, identify the renal pedicle. Clamp the left renal pedicle with a microvascular clip. Confirm the ischemia by a visible change in kidney color from pink to dark red.To avoid desiccation during clamping, cover the kidney with sterile saline-wet cotton balls. After 25 minutes, open the left microvascular clip to start reperfusion of the left kidney. Return the kidney to the abdominal cavity.Close the abdominal cavity with 6/0 absorbable suture materials. Observe the mouse until it begins to move freely and feed. Renal ischemia after renal pedicle clamping is shown here.A kidney color change from pink to dark red reveals that the kidney perfusion has become inadequate. Compared to the controls, serum levels of blood urea nitrogen and creatinine increased two days after renal reperfusion. This technique paves a way for researchers to explore novel therapeutic approaches against acute renal injury.

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1.8K visualizações.  Fu Jen Catholic University. A lesão renal aguda é um importante fator de risco associado à alta mortalidade em pacientes com parada cardíaca após retorno da circulação. Esse procedimento pode ser realizado para induzir lesão renal aguda. Esse protocolo consiste em induzir a reperfusão da isquemia renal de forma precisa, segura e consistente.Quem demonstrará o procedimento será Huang Cheng-Wei, um assistente do meu laboratório. Para começar, coloque um camundongo macho C57BL/6 anestesiado de oito sema...