Naked Science Forum

Life Sciences => Cells, Microbes & Viruses => Topic started by: raju_ayer on 12/04/2013 16:33:10

Title: What does spermatozoa need for metabolism?
Post by: raju_ayer on 12/04/2013 16:33:10

 Hi can you please tell me:

Spermatozoa in seminal fluid utilises the following sugar for its metabolism:
Fructose or galactose or mannose or glucose

thanks

Title: Re: What does spermatozoa need for metabolism?
Post by: cheryl j on 12/04/2013 20:49:01

My textbook says "fructose and other nutrients" from fluid made by the seminal vesicle. Prostate gland adds "citric acid, calcium and various enzymes."

Title: Re: What does spermatozoa need for metabolism?
Post by: evan_au on 13/04/2013 01:59:49

The energy for sperm to swim is provided by mitochondria in the sperm (mitochondria are often called the powerhouse of the cell).

However, these mitochondria in the sperm are almost never incorporated into the fertilised egg, which inherits its mitochondrial DNA from the mother.

See http://en.wikipedia.org/wiki/Sperm#Motile_sperm_cells

Title: Re: What does spermatozoa need for metabolism?
Post by: Zagami on 29/04/2018 15:14:31

Seminal fructose microassay according Karvonen and Malm, modified method
Principle
On heating and at low pH, fructose form a colored complex with indole, which absorbs light at 470 nm
Reagents
Deproteinizing reagent: dissolve 1.8 g (62.62 mM) of ZnSO4•7H2O or 1.124 g ZnSO4•H2O in 100 ml of dH2O
Alkalinized reagent: dissolve 0.4 g (0.1 M) of NaOH in 100 ml H2O
Chromogen reagent: dissolve 200 mg (16.38 mM) benzoic acid in 100 ml dH2O heating it at 60 °C in bath water and then dissolve 25 mg (2.13 mM) of indole. When completely dissolved leave to cool at 4 °C in continue mixing and storing at 4 °C.
Acid reagent: HCl concentrated 32-37%
Fructose standard: in 20 ml dH2O dissolve 117 mg (mM 6.5) fructose, add dH2O to 90 ml, dissolve 0.09 g of NaN3 and fill up to 100 ml with dH2O.
Procedure
Leave to fluidify seminal fluid and after, exactly to measure total volume of the seminal specimen, centrifuge the semen sample for 10 min. at 1000 g. Decant and store the sperm-free seminal plasma at 20 °C until analysis. Sperm-free seminal plasma can be pooled with other samples to provide a standard for internal quality control in future assays. Thaw the sperm-free seminal plasma, if it were frozen,  and mix well on a vortex mixer. Pipet in three 0.5 ml eppendorf test-tube, respectively 100 µl of supernatant, 100 µl fructose standard and 100 µl of dH2O (blank) and therefore add, in all tubes, 150 µl of deproteinizing reagent and 100 µl of alkalinized reagent. Mix and incubate for 5 - 15 min. at room temperature and then centrifuge to 1500 - 8000 g respectively for 20 - 5 min. Leaving a well of the MTP empty (for zero), working in duplicate, pipet from each respective supernatants, 50 µl and dispense in the relative wells. Then dispense 50 µl of chromogen reagent in each wells, followed by 140 µl of acid reagent in all wells. Shaking on horizontal mixer at 200 rpm for 5 sec., and sealing wells with adhesive plastic, incubate at 37 – 50 °C respectively for 30 – 20 min. Read the Abs at 470 nm, against zero well, using microplate reader.
Calcule      
To apply the following formula:
Fructose in total ejaculate (µM) = ((Absejaculate - Absblank /Absstandard - Absblank x 14)/1000) x SEV
In which: 14 = calculate value, taking account of the initial sample dilution and standard concentration; 1000 = conversion from mM to µM, and SEV = sample ejaculate volume
Normal value
According WHO are considered normal levels when fructose is ≥ 13 µM/ejaculate.