Innovative Methodology Quantitative imaging of basic functions in renal (patho)physiology
نویسندگان
چکیده
Kang, Jung Julie, Ildiko Toma, Arnold Sipos, Fiona McCulloch, and Janos Peti-Peterdi. Quantitative imaging of basic functions in renal (patho)physiology. Am J Physiol Renal Physiol 291: F495–F502, 2006. First published April 11, 2006; doi:10.1152/ajprenal.00521.2005.—Multiphoton fluorescence microscopy offers the advantages of deep optical sectioning of living tissue with minimal phototoxicity and high optical resolution. More importantly, dynamic processes and multiple functions of an intact organ can be visualized in real time using noninvasive methods, and quantified. These studies aimed to extend existing methods of multiphoton fluorescence imaging to directly observe and quantify basic physiological parameters of the kidney including glomerular filtration rate (GFR) and permeability, blood flow, urinary concentration/dilution, renin content and release, as well as more integrated and complex functions like the tubuloglomerular feedback (TGF)-mediated oscillations in glomerular filtration and tubular flow. Streptozotocin-induced diabetes significantly increased single-nephron GFR (SNGFR) from 32.4 0.4 to 59.5 2.5 nl/min and glomerular permeability to a 70-kDa fluorophore approximately eightfold. The loop diuretic furosemide 2-fold diluted and increased 10-fold the volume of distal tubular fluid, while also causing the release of 20% of juxtaglomerular renin content. Significantly higher speeds of individual red blood cells were measured in intraglomerular capillaries (16.7 0.4 mm/s) compared with peritubular vessels (4.7 0.2 mm/s). Regular periods of glomerular contraction-relaxation were observed, resulting in oscillations of filtration and tubular flow rate. Oscillations in proximal and distal tubular flow showed similar cycle times ( 45 s) to glomerular filtration, with a delay of 5–10 and 25–30 s, respectively. These innovative technologies provide the most complex, immediate, and dynamic portrayal of renal function, clearly depicting the components and mechanisms involved in normal physiology and pathophysiology.
منابع مشابه
Quantitative imaging of basic functions in renal (patho)physiology.
Multiphoton fluorescence microscopy offers the advantages of deep optical sectioning of living tissue with minimal phototoxicity and high optical resolution. More importantly, dynamic processes and multiple functions of an intact organ can be visualized in real time using noninvasive methods, and quantified. These studies aimed to extend existing methods of multiphoton fluorescence imaging to d...
متن کاملAdvances in renal (patho)physiology using multiphoton microscopy.
Multiphoton excitation fluorescence microscopy is a state-of-the-art confocal imaging technique ideal for deep optical sectioning of living tissues. It is capable of performing ultrasensitive, quantitative imaging of organ functions in health and disease with high spatial and temporal resolution which other imaging modalities cannot achieve. For more than a decade, multiphoton microscopy has be...
متن کاملMultiphoton imaging of renal regulatory mechanisms.
Most physiological functions of the kidneys, including the clearance of metabolic waste products, maintenance of body fluid, electrolyte homeostasis, and blood pressure, are achieved by complex interactions between multiple renal cell types and previously inaccessible structures in many organ parts that have been difficult to study. Multiphoton fluorescence microscopy offers a state-of-the-art ...
متن کاملEarly clinical exposure program in learning renal physiology
Introduction: Teaching renal physiology for undergraduatemedical students in an understandable way using methods whichimprove their deep learning has always been a problem. In thisstudy, Early Clinical Exposure (ECE) was used in teaching renalphysiology for the second year medical students in Shiraz MedicalSchool. This article aims to introduce and develop this programand also measure the attit...
متن کاملQuantitative microscopic approaches for studying kidney functions.
Intravital ratiometric microscopy is a powerful method for quantitative study of kidney functions. As demonstrated in the examples, both the generalized polarity and direct ratio imaging approaches allow investigators to address basic and important questions such as those related to filtration, permeability and reabsorption. Both approaches have similar advantageous for in vivo imaging. However...
متن کامل